BRPI0611222A2 - intravenous access and guidance system, and ultrasound sensor assembly - Google Patents

Abstract

GENTLE ACCESS AND DIRECTION SYSTEM, AND, ULTRASOUND SENSOR ASSEMBLY. The invention relates to the direction, positioning, and placement confirmation of intravascular devices such as catheters, stylets, guidewires, and other flexible elongate bodies that are typically percutaneously inserted into the venous or arterial vasculature. Currently, these goals are achieved using x-ray imaging and, in some cases, ultrasound imaging. This invention provides a method for substantially reducing the need for related imaging to place an intravascular catheter or other device. Reduced imaging needs also reduce the amount of radiation patients undergo, reduce the time required for the procedure, and decrease the cost of the procedure by reducing the time required in the radiology department. One aspect of the invention includes, for example, an intravenous access and targeting system. The system comprises: an elongated flexible limb adapted and configured to access a patient's venous vasculature; a sensor disposed at a distal end of the elongate flexible member and configured to provide non-imaging in vivo ultrasound information of the patient's venous vasculature; a processor configured to receive and process non-imaging in vivo ultrasound information of the patient's venous vasculature provided by the sensor and to provide position information regarding the position of the distal end of the elongate flexible member within the patient's venous vasculature; and an output device adapted to output position information from the processor.

Description

"GENTLE ACCESS AND DIRECTION SYSTEM, AND, ULTRASOUND SENSOR SET" CROSS REFERENCE

This application claims the benefit of provisional patent application US 60 / 678,209 filed May 6, 2005 by SorinGrunwald et al. Entitled "Method and Apparatus for Intravascular Catheter Guiding and Positioning" and provisional patent application US 60 / 682,002, filed May 18, 2005, also by Sorin Grunwald et al. entitled "Method and Apparatus for Intravascular Catheter Guiding and Positioning", both incorporated herein by reference in their entirety.

BACKGROUND OF THE INVENTION

The invention relates to guiding, positioning and confirming the placement of intravascular devices such as catheters, stylets, guidewires, and other elongate bodies that are typically percutaneously inserted into the venous or arterial vascular system, including flexible elongate bodies. affected by the use of x-ray imaging and, in some cases, ultrasound imaging. This invention provides a method for substantially reducing the need for image deformation relative to placement of an intravascular or other device catheter. Reduced imaging also reduces the amount of radiation to which the patient is subjected, reduces the time required for the procedure, and decreases the cost of the procedure by reducing the time required in the radiology department.

The mammalian vascular system has been accessed to provide therapy, administer pharmacological agents, and meet other clinical needs. Numerous procedures exist in both venous and arterial systems and are selected based on patient need. A challenge common to all vascular-based therapies is for the healthcare provider to access the specific site or section of the vascular tree.

A common venous access procedure is venous access. Central venous access is the placement of a venous catheter into a vein that leads directly to the heart. Central venous catheters are generally present in the medicine of modern hospitals and outpatient clinics, with up to 8 million insertions per year in the US and a similar number forced into the US.

Venous access devices are most commonly used for the following purposes:

• Administration of medications such as antibiotics, chemotherapy drugs and other IV drugs

• Administration of fluids and nutritional compounds (hyperalimentation)

· Blood product transfusion

• Hemodialysis

• Multiple blood draws for diagnostic tests

Venous access devices are small flexible tubes placed in large veins of people who need frequent access to their blood vessels. Devices typically remain for long periods; week, month or even longer.

Central venous access devices are usually inserted in 1 of 3 modes:

a) Directly via a catheter. Catheters are inserted through the skin under the skin in the subclavian vein (located under the daclavicular bone) or the internal jugular vein (located in the neck). The part of the catheter in which medications are administered or blood is collected remains outside the skin.

b) Through a hole. Unlike catheters, which come out of the skin, ports are placed completely below the skin. With a door, a high disc around the size of a 25-cent dollar coin is felt under the skin. Blood is collected or medicine is dispatched by placing a thin needle through the overlapping skin in the container or reservoir.

c) Indirectly via a peripheral vein. Peripherally inserted catheter-central lines (PICC), unlike catheters and central doors, are not inserted directly into the central vein. A PICC line is inserted into a large vein in the arm and advanced into the subclavian greater vein.

Catheters and central ports are usually inserted by a surgeon or surgical assistant in an operating room. An alternative is placement under the guidance of a special x-ray machine so that the person using the line can be sure that it is properly placed. A PICC line can be placed at the bedside, usually by a specially trained nurse. In the latter case, x-ray confirmation is currently required to assess the success of PICC placement.

Traditional surgically placed central catheters are increasingly being replaced by peripherally inserted central venous access devices. PICC lines typically cause less severe complications than central venous access devices. Peripherally Inserted Cathetercentral (PICC) is sweaty in a variety of clinical procedures. The PICC line placement procedure is performed by interventional radiologists to deliver long-term drug delivery, chemotherapy procedures, intravenous drug delivery or intravenous nutrition (hyperalimentation) and blood sample collection via a Hickman catheter. PICC insertion is a routine procedure because it is performed quite often for a variety of treatments, and more than once in the same patient when the catheter is to be left in place for a period of time. Although it is a routine, it is a very time and labor intensive procedure for hospital staff, which makes it also costly.

During the procedure, the doctor or nurse places the catheter into a superficial arm vein such as the cephalic, basilar, antecubital, median, or other superficial vein, with the aim of having the distal end of the catheter reach the superior vena cava. After entering the superficial vein around the area where the arm bends (elbow), the catheter is advanced to the subclavian vein, after which the brachycephalic vein and finally enters the superior vena cava. One caution is to make sure that the PICC line does not enter the jugular vein via subclavian oats.

Hemodialysis therapy via a hemodialysis catheter is another example of a procedure requiring central venous access. A dialysis catheter is a special type of central venous catheter used in dialysis. Dialysis catheter placement involves inserting a catheter into a vasogrand using x-ray guidance. The challenges of inserting a hemodialysis catheter in terms of guidance and positioning are similar to those of a central venous catheter, but are typically larger and require a detachable insertion sheath.

Another therapy obtained via providing access to the venous system is percutaneous treatment of varicose veins. Population studies published indicate that approximately 25 million people in the US and 40 million in Western Europe suffer from symptomatic venous reflux disease. Percutaneous treatment of varicose veins involves the placement of an energy delivery catheter (laser or RF) after navigating the vascular system to locate the treatment site. A common site of treatment is the spheno-femoral junction, and less common sites are the pho-popliteal junction and perforating vein sites, which connect the superficial venous system to the deep venous system of the leg in a variety of different locations, especially below the knee. Thus, in the case of percutaneous treatment of varicose veins using specific venous junctions, the position of the laser or RF catheter at the optimal location with respect to the venous junction is critical to the success of the intervention. Currently, x-ray or ultrasound imaging or both are used for such positioning.

In addition to guiding the catheter through the vascular system, localization of the catheter tip is very important for the success of the procedure. Catheters will generally work equally well for pressure measurement and fluid infusion if the tip is located in any major vein, above or below the heart. For dialysis or infusion of irritating / hypertonic fluids, a high blood flow rate passing through the catheter tip is desirable, and this requires placing the lumen opening in as large a vessel as possible. However, the bundle inserts of many central venous catheters present important warnings about the absolute requirement that the catheter tips lie outside the heart to prevent perforation and subsequent pericardial tamponade. Likewise, opposition of the catheter tip outside the small peripheral veins is important to avoid damage to the vein wall or vein occlusion due to caustic effects of the infusion solution. It is also of greater interest that the catheter points remain in place after placement for the entire duration of the treatment. If the tip of the catheter moves, not only is its effectiveness diminished, but in some situations it can puncture the heart. In the US, the Foodand Drug Administration issued a warning emphasizing this point. Typically, interventional oradiologist uses a fluoroscopic agent to delineate veins in the body and subsequently verify the correct placement of the catheter tip using a postoperative x-ray. Currently, postoperative x-rays are routinely performed, while some studies have shown that only 1.5% of cases are subject to complications that would undoubtedly require x-ray imaging.

What is needed are methods and apparatus for optimizing eagle and catheter placement to reduce the risk associated with erroneous placement and the cost associated with x-ray imaging. In addition, there remains a need for a catheter guide and placement system that can be used to safely guide and place catheters in depressing health or clinical settings other than in a radiological department or surgical room where a radiological imaging or other modality is formed. external image is used to confirm placement of the catheter. Thus, the need remains in the medical art for instruments, systems and associated methods for locating, guiding and placing catheters and other instruments in the general vascular system. In addition, there remains a need in the medical art for instruments, systems, and associated methods for locating, guiding, and placing catheters and other instruments in the vascular system to meet the challenges presented by the unique features and attributes specific to the vascular system of interest.

SUMMARY OF THE INVENTION

One aspect of the invention includes an intravenous access and guide system. The system comprises a flexible limb adapted and configured to access a patient's venous vascular system; a sensor arranged at a distal end of the elongate flexible limb and configured to provide in vivo ultrasound information not based on the patient's venous vascular system; a processor configured to receive and process in vivo ultrasound information not based on the patient's venous vascular system image provided by the sensor and provide position information with respect to the position of the elongated flexible distal extremity within the patient's venous vascular system; It is an output device adapted to produce position information from the processor. In some embodiments, the device is further adapted to provide a catheter, guidewire, and / or stylus. In other embodiments, the device is adapted to deliver therapy to a patient, or to provide venous access to another device. In yet another embodiment, the system is adapted to further comprise a sensor clamping mechanism adapted to releasably detach the limb sensor elongated flexion while the elongated limb remains in the patient's venous vascular system. In yet another embodiment, the system is configured such that the processor processes in vivo ultrasound information not based on the image of the patient's vascular system provided by the sensor to indicate in the output information the proximity of the sensor to a structure within the patient's vascular system. . In still other embodiments, the processor may be further configured to process non-imaging in vivo ultrasound information of the patient's vascular system to indicate, in the output information, movement of the elongate flexible member in a desired direction within the vascular system of the patient. Alternatively, the processor is further configured to process non-imaging in vivo ultrasound information of the patient's vascular system based on a parameter selected from a group consisting of: a venous blood flow direction, a venous blood flow velocity, a venous blood flow signature pattern, a pressure signature pattern, A-mode information, and a preferred non-random flow direction. In another aspect of the invention, the system further comprises a divergent sensor associated lens, or a plurality of sensor associated lenses. The diverging lens may be adapted to couple the sensor to the elongate flexible member. The sensor may further be configured to be the first sensor adapted to transmit an ultrasound signal, the system further comprising a second sensor adapted to receive non-image based ultrasound information. Additionally, a step-down drive mechanism adapted to drive the sensor in a plurality of ultrasound transmission modes may be provided. In some embodiments the step-down sensor is a first sensor, the system further comprising a second sensor arranged at the distal end of the flexible member. lengthened and configured to provide non-imaging in vivo ultrasound information of the patient's venous vascular system to the processor. In other embodiments, a centering element adapted to substantially center the distal end of the elongate member within a vessel. In some cases, two or more additional sensors, where the sensor and two or more additional sensors are coupled to the elongate flexible member in an arrangement that mimics an endovascular junction. Additionally a steering element to direct the device tip in response to derived feedback information. of the data acquired. Other embodiments may include a torque control element to direct the tip of the device in response to feedback feedback derived from the acquired data.

According to another aspect of the invention, an endo vascular access and guide system, comprising: an elongate flexible member adapted to access a patient's vascular system; a sensor and associated divergent lens disposed at a distal end flexible limb elongated and configured to provide non-imaging in vivo ultrasound information of the patient's venous vascular system, a processor configured to receive and process non-living in vivo ultrasound information image-based relative position of elongated flexible distal extremity within the patient's venous vascular system; An output device adapted to produce the position information of the processor is provided. The elongate flexible member may be adapted to comprise a catheter, guidewire, or stylet. In some embodiments, the system may further be adapted such that the elongate flexible member is adapted to deliver therapy to the patient and / or provide vascular access to another device. In still other embodiments, a sensor coupling mechanism adapted to releasably detach the elongate flexible member sensor while the elongate flexible member remains in the patient's vascular system. Some embodiments of the system may be adapted such that the processor is further configured to process in vivo ultrasound information not based on the patient's vascular system image provided by the sensor to indicate, in the output information, the proximity of the sensor to the structure within the system. patient's vascular In some cases, the processor is further configured to process non-imaging in vivo ultrasound information of the patient's vascular system to indicate, at the exit information, movement of the elongate flexible limb in a desired direction within the patient's vascular system. In other cases the processor is further configured to process non-imaging in vivo ultrasound information of the patient's vascular system to indicate in the output information the proximity of the sensor to a structure within the patient's vascular system. In still other cases, the processor is further configured to process non-imaging in vivo ultrasound information from the patient's vascular system based on a parameter selected from a group consisting of a blood flow direction, a blood flow velocity, a blood flow signature, a pressure signature pattern, A-mode information, and a nonrandom preferential flow direction. The divergent lens may be adapted in some embodiments to couple the sensor to the elongate flexible member. In other embodiments, the sensor is a first sensor adapted to transmit an ultrasound signal, the system further comprising a second sensor adapted to receive non-image based ultrasound information. In still other embodiments, the sensor is a first sensor adapted to receive non-image based ultrasound information, the system further comprising a second sensor adapted to transmit an ultrasound signal. The system may also be adapted to comprise a sensor activation mechanism adapted to activate the sensor in a plurality of ultrasound transmission modes. In some embodiments, the sensor is a first sensor, the system further comprising a second sensor disposed at the distal end of the elongate flexible member and configured to provide non-imaging in vivo ultrasound information from the patient's venous vascular system to the processor. In other embodiments, the endovascular guide access system is adapted to further comprise a centering element adapted to substantially center the distal end of the elongate member within a vessel. The system may further comprise a guide member for directing the tip of the device in Response to Feedback Data Derived from Acquired Data. In other embodiments, the system may be adapted to further comprise a control element such as to direct the tip of the device in response to feedback feedback derived from the acquired data. In still further embodiments, the system comprises a plurality of lenses associated with the sensor.

Another aspect of the invention includes an ultrasound sensor assembly comprising: an ultrasound sensor; a transparent, ultrasound-proof seal encapsulating at least one side of the ultrasound sensor. The sensor assembly can be configured to include air-tight and transparent ultrasound sealing modeled on an acoustic lentacle. The acoustic lens may be adapted to be modeled to spread a beam generated by the ultrasound sensor. In some performance modes, the lens is made of epoxy. Other embodiments of the invention include an ultrasound sensor formed of a piezoelectric crystal, a piezoelectric ceramic, silicon, and / or a thin piezoelectric film. The system lens, in some embodiments, comprises a plurality of coils. In another aspect of the invention, the ultrasound sensor is coupled to the catheter to provide a forward directed beam, and / or a laterally directed beam. In other embodiments, the ultrasound sensor is disposed in a recess formed in a catheter wall. The ultrasound sensor may, in some embodiments, be adapted to perform Doppler readings of a fluid passing over the outer surface of the catheter. In some aspects of the invention, an air-tight and transparent ultrasound seal modeled on a lens acoustics is provided. The acoustic lens is modeled in some embodiments to spread the beam generated by the ultrasound sensor.

Still another aspect of the invention includes a method for placing an instrument in the venous system of a body. The method comprises the steps of: accessing the venous system of the body; position an instrument in the venous system of the body; use the instrument to transmit an ultrasound signal to the body's venous system; use the instrument to receive a reflected ultrasound signal from the vascular system indicating deluxe rates between 2 and 20 cm / s; processing the reflected ultrasound signal to determine one or more parameters of a group consisting of: a venous blood flow direction, a venous blood flow rate; a venous blood flow signature pattern; an A-mode information depression signature pattern; and a preferred non-random flow direction; and advancing the instrument within the vascular system using one or more parameters determined within the vascular system. Using the instrument to transmit an ultrasound signal to the body's vascular system comprises, in some aspects of the invention, transmitting or receiving an A-mode ultrasound signal to or from the body's vascular system. In some embodiments, using the instrument to transmit an ultrasound signal to the body's vascular system comprises transmitting or receiving Doppler ultrasound signal to or from the body's vascular system. In other embodiments, using the instrument to transmit an ultrasound signal to the body's vascular system comprises transmitting or receiving a non-imaging target tracker ultrasound signal to or from the body's vascular system. In some embodiments, processing the reflected ultrasound signal to determine a flow pattern determines a flow direction within the vascular system toward the instrument and additionally processing the reflected ultrasound signal to determine a flow pattern determines a direction. opposite flow to the instrument. In other embodiments, the reflected ultrasound signal is processed to determine the presence of a signal indicating a specific blood flow pattern; In still other embodiments, processing the reflected ultrasound signal is performed to determine the pressure of a signal indicating a specific pressure pattern. In still other embodiments, the reflected ultrasound signal is processed to determine the position of the instrumentorelative to the cavo-atrial junction. Other aspects of the invention may include processing the reflected ultrasound signal to determine the presence of flow after processing the reflected ultrasound signal to determine the presence of both anterograde and retrograde flows. Further aspects may further comprise processing the reflected ultrasound signal to determine the presence of flow opposite the instrument and after processing the reflected ultrasound signal to determine the presence of flow both opposite and toward the instrument. In some embodiments of the method, the method comprises processing the reflected ultrasound signal to determine the presence of a signal indicating a specific structure. In other aspects of the invention, the specific target vascular system for positioning the instrument is included, for example, the specific structure is a heart valve, a blood vessel wall, a heart wall. In another aspect of the invention, the method is additionally processing the reflected ultrasound signal to determine the presence of a signal indicating a position at which two or more vessels join. For example, the two or more vessels may comprise an upper vena cava and an inferior vena cava., An inferior vena cava and one vein; a common right iliac vein and a common left iliac vein; an external iliac and an internal iliac; a right brachycephalic vein and a left one; an superior vena cava and an aziga vein; a femoral vein commonly a large saphenous vein; a superficial and deep femoral vein, a popliteal vein and a smaller saphenous vein; a perforating vein and a superficial umve; a perforating vein and a deep tibial vein; a large saphenous vein and a varicose vein; a jugular vein and a subclavian vein; or a cephalic vein and an axillary vein. In another aspect of the invention, the method may further comprise using the instrument to determine a location for securing a device within the vascular system of a body; and securing the device to the body to hold the device at the location determined by the instrument. In yet another aspect of the method, the method may further comprise: using the instrument for comparing the calculated current position of the device; and determine if the device is at the location determined by the instrument. In some aspects of the method, it further comprises processing the reflected ultrasound signal to determine the position of the instrument within the atrium relative to the coronary bell. In yet another aspect, the method further comprises processing the reflected ultrasound signal to determine the position of the instrument within the left atrium relative to a pulmonary vein.

INCORPORATION BY REFERENCE

All patents, publications and patent applications referenced herein are incorporated herein by reference in their entirety, to the same extent as if each individual patent, publication or patent application were specifically and individually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF DRAWINGS

The novel features of the invention are set forth in the appended claims. A better understanding of the features and advantages of the present invention will be achieved by reference to the following detailed description which illustrates embodiments in which the principles of the invention are used and accompanying drawings in which:

Fig. 1 is a diagram showing an overview of the technical and physiological differences between the venous and arterial systems;

Fig. 2 shows the main components of a realization mode of the inventive multi / single beam ultrasound processing system. A guided vascular access device, a system for processing signals from the guided vascular access device and a user interface;

Fig. 3 is a flow chart showing an example of the catheter placement method;

Fig. 4 shows a portion of a pectoral cavity showing a correct position for the catheter in the basilic vein;

Fig. 5 is a table summarizing some of the features of the devices of the invention;

Fig. 6 is a graph depicting features of directionally and non-directionally guided vascular access devices. FIG. 6Α is a planar view of the catheter guidance system for use with directionally guided vascular access devices including an oximeter catheter;

Fig. 6B shows an enlarged view of a portion of the embodiment of Fig. 6A, shown cut away;

Fig. 6C is a side view of a multi / single beam ultrasound guide catheter of the present invention with an electrophysiological catheter within the guide catheter and two thumb sliders to guide the guide catheter;

Fig. 6D is a side view of a multi / single beam ultrasound guide catheter of the present invention with an electrophysiological catheter within the guide catheter and four thumb sliders (only three of them shown) to direct the catheter. guide catheter;

Fig. 6E is a cross-sectional view of the guide catheter body of the

Figs. 6C and 6D;

Figs. 6F-G are planar views of the distal portion of a guidewire according to an exemplary embodiment of the present invention;

Fig. 7 shows an embodiment of the invention having four sensors at the distal end of a catheter;

Fig. 8A and 8B show terminal and sectional views of a guided multi-sensor catheter-based vascular access device

Figs. 9A through 9D show a catheter-based guided vascular access device centering device;

Figs. IOA through IOC show a catheter-based vascular access device having a preformatted shape;

Figs. 1IA-B show an embodiment of the invention as a sensor disposed in a recess of the elongate body;

Figs. 12A-B show an embodiment of the invention wherein the sensor is disposed at the distal end of a closed catheter end;

Figs. 13A-C show an embodiment of the invention in which sensors are disposed on the distal end of the catheter and a sensor is disposed on the side of the catheter;

Figs. 14A-E show a variety of sensor array arrangements;

Fig. 15 shows the tip of a stylus, or other elongate body, with sensors positioned at its distal end;

Figs. 16A-B show the tip of a stylus, or other elongate body, in which a seal covers the sensors;

Fig. 17 shows an array of microlenses attached to a sensor;

Figs. 18A-C show the use of a locating device with a guidewire;

Figs. 19A-B show a sensor disposed on a convex side of a distal portion of a guidewire;

Fig. 20 shows sensors on both sides, concave and convex from the distal portion of a curved guidewire;

Figs. 21A-B show a guidewire having a distal portion in the form of a hockey stick with a sensor positioned thereon;

Figs. 22A-B show a sheath for use in introducing the guidewire of Figs. 20-21;

Figs. 23A-B show an embodiment of the invention, wherein a plurality of sensors are disposed at the distal end of a stylus;

Fig. 24 shows an embodiment of the invention wherein the guided vascular device is a stylus with two sensors at the distal end; 25 shows a block diagram of additional components within a control and acquisition unit;

Fig. 26 shows a flowchart of an algorithm implemented by a multi / single beam ultrasound;

Fig. 27 shows a block diagram of an embodiment

of a multi / single beam ultrasound system;

Fig. 28 shows the use of correlation methods in a tracking algorithm for the target velocity;

Fig. 29 shows a preferred embodiment of a tracking method for processing a real time signal input;

Fig. 30 shows an embodiment having a waveform synthesizer;

Fig. 31 shows some specific properties of an ultrasound beam generated by a sensor as a result of an excitation;

Fig. 32 shows electronic pulses generated by a waveform synthesizer where each sensor can be directed, in real time, in a sequence of operating modes;

Fig. 33A shows a single waveform pulse at an operating frequency; Fig. 33B shows a coded excitation;

Figs. 34-42 show techniques for positioning a device according to the invention within the venous system;

Figs. 43A-B show a parameter of the multi / single beam ultrasound system of the present invention;

Fig. 44 shows a force vs. strength curve. frequency;

Fig. 45 shows a transition from venous flow to a change in atrial flow;

Fig. 46 shows a representative signal detected by a system when a device according to the invention is positioned in the right atrium; 47 shows a standard signature sequence that can be used to reliably and accurately identify the pathway from the superior vena cava to the coronary sinus;

Fig. 48 shows an invention guided vascular access device at the saphenofemoral junction;

Fig. 49 shows a user-specific interface path with LED indicators;

Figs. 50A and 5OB show a basic user interface with control lights;

Figs. 51 and 52 show components of a system according to the invention; and

Fig. 53 shows the possibilities of local detection of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the invention provide guided vascular access devices, systems for processing signals from guided vascular access devices, and the user interface for providing information to a user based on the outputs of the processing system. Other aspects of embodiments of the invention relate to the use of intravascularly measured physiological parameters to locate, guide and place catheters in the vascular system (see Fig. 1). In one aspect, the present invention relates to a catheter assembly with built-in sensors to measure physiological parameters such as flow, velocity and blood pressure. In a different aspect, the present invention relates to data processing algorithms that can identify and recognize different locations in the vascular system based on the pattern of physiological parameters measured at this location. In a third aspect, the present invention relates to an instrument that has a user interface that shows targeting and positioning information. The fourth aspect of the present invention relates to the method for guiding and positioning a catheter within the vascular system by the user based on the location information provided by the catheter itself. Other aspects of embodiments of the invention relate to the use of intravascularly measured physiological parameters to locate, guide and place catheters or guidewires, as guides for particular locations within the vascular system that have been identified using the devices. vascular access systems and systems described herein.

The present invention provides a novel apparatus and method for intravascular targeting and catheter placement and for monitoring its localization within the vasculature based on recognition of blood flow patterns at sites of interest. A major benefit of the new device and method introduced in it is that it increases the chances of proper placement of devices in a bedside procedure if there is a need for direct imaging, in particular X-ray imaging. Another benefit is related to the fact that that targeted vascular access devices and systems can be inserted into the existing health care workflow to place instruments in the vasculature. More specifically, a novel method and method for intravascular guidance and catheter and / or guidewire placement is then directed to the development of other outer body devices such as, for example, heart valve location for heart valve replacement; identification of renal and inferior veins for IVC filter placement; localization of coronary sinus for placement of mitral valve modification devices or bypass leads; localization of pulmonary veins for sensor placement and / or delivery of therapy such as ablation treatment for atrial fibrillation, as well as device placement or delivery of therapy at specific locations in the vasculature identified by techniques described herein. In some embodiments, systems and methods Of the inventive guidance system described herein, paralyzing, guiding, and positioning catheters and / or guide wires equipped with sensors described herein are used within venous system vessels. The embodiments described herein may also be used in the arterial system vessels as well. In one aspect, the guided vascular access devices described herein can be used to confirm the direction, positioning and placement of intravascular catheters used in a large number of clinical applications. Examples of clinical applications that could benefit from embodiments of the invention include placement of, for example, central venous access catheters, hemodialysis catheters and placement of catheters or therapeutic devices or treatment systems for percutaneous treatment of varicose veins.

The present invention is based on the ideas that: a) certain locations in the vascular system can be identified by specific blood flow patterns at these locations when quantified by blood pressure or Doppler measurement; and b) the direction of travel of a catheter can be determined relative to the direction of blood flow using the Doppler effect.

For example, in the case of a PICC line, by determining and monitoring in real time the direction of catheter movement in the vasosanguines using the sensors, techniques, data acquisition, and processing described herein, the user receives feedback when advancing. guided vascular access device to allow the PICC to advance along a desired path from the arm vein to the vena cava. The system can also recognize accidental inputs in other veins due to differences in flow patterns received from the sensors. As such, the system may recognize accidental entry into the jugular vein, subclavicular vein or even the sensor is against the vessel wall. By monitoring acquired data from sensors positioned on the guided vascular access device, the user may be notified when the catheter tip reaches the ideal placement point near the root of the vena cava. The system recognizes the root of the vena cava and other vascular components, analyzing the data acquired by the sensor to identify unique patterns and signatures.

The technology described herein is essentially non-imaging, that is, it does not need all the elements that make imaging possible, for example scanning with moving transducers or working with phased arrangements and beam forming. Non-image based ultrasound refers to a dimensional representation of ultrasound information. In contrast, imaging ultrasound utilizes 2D or 3D ultrasound information, moving transducers, arrays, phased array techniques, and beam deformation. As such, embodiments of the present invention provide a venous ultrasound-based guidance system for: endovascular characterization of venous blood flow; venous catheter guidance; endovascular characterization of smooth-moving anatomic targets; provide a disposable ultrasound data acquisition unit (used only once); and provide a simple, inexpensive, portable user interface.

Most previous designs for the use of ultrasound for diagnostic and therapeutic purposes lead to problems on the arterial side of the vascular system where blood flow velocities are higher and the diameters of the arteries are lower than their accompanying counterparts (Fig. 1). As such, data processing devices and algorithms that are developed for the arterial circulation do not work well within the venous circulation, where blood flow velocities are typically in the range of 2-15 cm / sec rather than 40-80cm / sec. second as in normal arteries. Similarly, for catheter-based ultrasound devices to function within venous circulation, a lower dual-sound operating frequency of approximately 10 MHz is required and a larger sample size (depth) is required than on the arterial side. .

An example of an arterial ultrasound system, as described by Franzin in "Doppler-guided retrograde catheterization using guidewire-equipped transducer" (US Patent 5,220,924), uses a 20 MHz single crystal pulsed wave (PW) Doppler to detect peak velocities in pulsatile flow in the arteries. Arterial measurement systems such as this system do not work for venous system applications (see Fig. 1), such as PICC insertion targeting, for several reasons. One reason is that the depth of penetration of such systems is inadequate. The depth of ultrasound penetration in tissues, including blood, is at most about 3 - 5 mm with an operating frequency of 20 MHz. This penetration depth is not deep enough to measure velocities in vessels with internal diameters of 10–10 mm. 20 mm or larger, as in SVC or in other veins with larger diameter. Furthermore, such a system, with an operating frequency of 20 MHz, is not able to characterize the flow and determine the cavo-atrial junction which may need up to 15 mm penetration depth. In order to be able to monitor the high peak velocities of the arterial system, where blood flow of approximately 15 cm / s is expected, a parameter called pulse repetition frequency (PRF) must be relatively high, potentially higher than 100 kHz. In contrast, peak velocities of the venous system, where a blood flow of approximately 15 cm / s is expected, the PRF parameter may be approximately 40 kHz to successfully characterize such relatively slow blood flow.

A third reason, related to PRF, involves the relatively large size of the sample volume required to characterize, accurately, venous blood flow patterns according to inventive process techniques described herein. The 100 kHz PRF, required for high speed detection, produces a sample volume size in the order of approximately 2 mm wide. Such a sample volume size is totally inadequate for the accurate characterization of blood flow patterns in the larger veins. A sample volume of approximately 15 mm is required for the characterization of large veins and further modifications are required to ensure adequate depth of penetration is obtained.

A fourth reason why conventional arterial ultrasound systems are not appropriate for the venous system monitoring techniques described here is that arterial systems are optimized to detect high blood flow velocities or even only peak velocities. Using Franzin's arterial system as an example, such an arterial monitoring system should detect only the velocities of the peak flow peaks and not the entire velocity pattern. Arterial systems are not configured to discriminate at low speeds or to detect flow patterns containing slow velocities, for example venous flow.

RELEVANT ANATOMIC AND PHYSIOLOGICAL CONSIDERATIONS

For placement of intravenous lines of venous flow along the placement pathway is of importance, for example, from basal and cephalic veins to the subclavial, branchial, and interior veins.

The superior and inferior vena cava are known as "large veins" and are of special interest for central venous access applications. Their combined internal diameters in the right atrium are between 2.5 and 3 cm and their combined transverse area is approximately 6 cm2. The blood velocities in the large veins can reach 15 cm / s to allow a blood flow of approximately 5 l / min. These are the highest speeds on the venous side. From the heart, towards the capillaries, venous velocities decrease because the total transverse area of the vasosanguins increases, while the amount of blood flowing is the same. In the basilar or cephalic veins, blood flows at approximately 2 to 5 cm / s. . Venous flow is non-pulsatile. Variations are small and due mainly to the propagation mechanism aided by locally distributed venous valves and the effect of respiration that alters blood flow velocities within the deep and central veins, proportional to changes in intrathoracic and intra-abdominal pressures.

In comparison, on the arterial side and in the heart, blood flows at around 50 cm / s and can reach a peak velocity of 80 cm / s. Average velocities are higher in arteries than in veins, due to the fact that arterial flow is pulsatile, with high peak velocities. The pulsatile pattern of arterial flow follows the pulsatile pattern of the heartbeat, which represents the centralized mechanism of blood propagation through the arteries.

The table below summarizes the parameters that can be used to characterize blood flow and the differences between these parameters in venous, arterial, and heart chamber flows. Because of these differences, different requests are imposed on technology to characterize fluxovenous vs. arterial or chamber flow of the heart.

TABLE 1

<table> table see original document page 25 </column> </row> <table>

Fig. 2 schematically depicts the components of the endovascular access and guide system. A sensor is coupled to a catheter and connected via an electrical connection through a catheter lumen to an external connector. The external connector is connected to a signal processing unit which can identify the location of the sensor in the vascular system based on the physiological parameters of said location. The signal processing unit is connected to a user interface.

A catheter assembly is provided having a sensor attached to the catheter tip (distal end). The sensor may be a pressure, Doppler or temperature sensor, or any other type of sensor that may be used to detect physiological parameters within the blood vessel. A phi-metallic is connected to the sensor, providing an electrical sensor connection to the outside of the body. This can be achieved, for example, through an electrical connection passing through the catheter wall or lumen sensing to a connector placed at the proximal end of the catheter. The catheter assembly containing a sensor may be made in a variety of ways and is described in more detail below.

Connector 1 in Fig. 2 provides a means for electrically coupling the catheter assembly to a data acquisition and processing device. Possible components of a data acquisition and processing device include an electrically or wirelessly matched connector 2 with catheter assembly connector 1, a data acquisition and control unit, desinal processing unit, basic user interface and another interface unit.

In one embodiment, the catheter assembly is used sterile while the device is non-sterile. Therefore, the device has to be packed in a sterile pouch prior to disposal. The connector provides a means for puncturing the pouch and for connecting the device to the sterile pouch so that sterility is ensured for operation of the device in the sterile field. In another embodiment, the device is sterile and is coupled to the sterile catheter directly.

The device implements the fingerprint processing algorithm and indicates to the user the location of the vascular tree catheter or catheter tip, a user interface or display. In a realization mode, the user interface may have colored lights that indicate affixing or status of the guided vascular access device within the vascular system. For example, a green light may indicate blood flow as opposed to the guided vascular access device, meaning that the access device Guided vascular therapy is being in the right direction or desired, for example, toward the heart in some applications. A red light may indicate blood flow toward the guided vascular access device, meaning that the guided vascular access device is being advanced the wrong way or away from the heart. A blue light may indicate that a blood flow pattern or other signature or unique appearance has been detected, indicating that the guided vascular access device is near the desired position within the vascular system. The desired location can be any within the vascular system where ultrasound multi / single-beam processing techniques and guided vascular access devices can detect a blood flow pattern or other unique signature, aspect or anatomical landmark. For example, guided vascular access devices described herein may be used to identify the junction between the vena cava and the right atrium (see, for example, Figs. 38, 39, 41,42), the saphenofemoral junction (see, for example). , Fig. 48) or other portions of the vascular system identifiable by the use of water-written systems and methods. In addition, the invention allows the catheter to be self-guided without the need for an external imaging modality such as fluoroscopy or ultrasound that is currently required with existing catheters.

Fig. 3 illustrates an example of decatheter placement method 300. In this example, method 300 describes how a user would place a PICC catheter using a guide information guided vascular device provided by the use of multi / single ultrasound beam system and processing techniques described in more detail below. This example is for illustration purposes only. Catheter, guidewire, or similar conventional device introduction procedures can be tailored to the requirements of other therapeutic devices such as hemodialysis catheter placement, as well as placement of laser catheters, RF, and others for percutaneous treatment of varicose veins, among others, described in more detail below.

Although the techniques described herein may be practiced in various clinical arrangements, the placement method 300 will be described for bed side catheter placement. The working scheme presented in the catheter placement method 300 begins at step 305, measuring the approximate length of catheter required. This step is recommended for checking the location indicated by the device. This step is currently performed by the medical professional at the beginning of the procedure.

Then, in step 310, the sterile catheter is removed from the packaging with the insertion wire inserted and the sensor attached. In a preferred embodiment, the packaged catheter already contains a styletemodified with Doppler sensors. Currently, some PICC catheters are already packaged with stylets that are used by medical professionals to push the catheter through the vascular system. Currently, these catheters and their stylets do not contain any sensors.

Then, in step 315, the non-sterile user interface housing is attached by packing it into a sterile pouch and perforating it with the connector end of the delivery wire. In a preferred embodiment, the catheter containing the stylus with the sensor is sterile and disposable, while the user interface, control and signal processing unit are reusable and potentially non-sterile. If the unit is not sterile and cannot be used in the sterile field, it should be stored in the pouch using a commercially available sterile pouch. The catheter is then connected to the user interface unit by piercing the sterile pouch with the stylus connector. Alternatively, a sterile wire or cable may be passed into a forced sterile field and subsequently coupled to a non-sterile control unit without having to puncture a pouch. Other decomposing connection aspects are described below with respect to Figs. 51 and 52.

Then, in step 320, the self-test button is pressed on the user interface housing and waited to see the LED flash. Once the sensor is connected, the system can perform a self-test protocol to check the connection and sensor.

Then, in step 325, the catheter is inserted into the vessel. This step is similar to the catheter introduction currently performed by medical professionals. A preferred point of insertion into the basilica is indicated by "1" in Fig. 4.

Then, in step 330, it remains in position until the green light stops flashing (for example, it becomes a static green light). Once the recovery boiler is in the vessel, it should be held in position for a few seconds or slowly pushed forward. This step ensures that the signal processing algorithm can calibrate data acquisition and pattern recognition for current patient data. In addition, the processing system will analyze the sensor date to confirm that the sensor is placed in a vein rather than an artery. This placement confirmation aspect is described in greater detail below with respect to Fig. 34. Then, in step 335, after receiving confirmation from the system that the sensor / catheter has been introduced into a vein, the user may start advancing the catheter and observe the green light stays on. IF green light is on, blood flows oppositely to the catheter tip. The "green light" indication is the desired indication as the catheter / sensor is advanced to the thin position. Fig. 4 shows a correct catheter position in the basilic vein marked "Green" and meaning that the green light is on.

Then, at step 340, if the light turns red, the advance is stopped and the catheter pulled back until the light becomes green again. The light turns red when blood flows toward the catheter / sensor instead of oppositely. This means that the catheter was accidentally advanced into the jugular or other vein. In Fig. 4, this position is indicated as "Red" and the catheter is shown in the internal vein. In this situation, the blood stream flowing toward the heart comes toward the device. In this situation, the recovery boiler must be pulled back to the position indicated by "2" in Fig. 4 and advanced again along the correct path to SVC. If accidentally the catheter is facing a vessel wall and cannot be moved, the light turns yellow: position marked "yellow" in 4. In this situation, the catheter should be pulled back until the yellow light is turned off and the green is turned on again.

Then, in step 345, it advances while the green light is on. The user maintains the push while the catheter / sensor remains on the proper path toward the heart.

Then, in step 350, the user stops advancing when the light turns blue. As shown in Fig. 4, the Iuza turns to blue when the lower third of the SVC has been identified. Light passes to blue when the processing system identifies the unique flow pattern or physiological parameters corresponding to the targeting region. In the illustrated method, the exclusive nature of the flow signature at the junction of the superior vena cava and the right atrium is identified and the blue indicator light illuminated. Techniques for determining the location of these unique flow signature locations are described in more detail below, with reaction to Figs. 34-40.

Then, at step 355, the user can verify the actual length against the initially measured length. This step is used to double check the indication provided by the device and compare it to the expected length initially measured for the octave position.

Then, in step 360, the attached stylus and sensor are removed.

Then, at step 360, the introducer is peeled off and then at step 370, the catheter is attached.

GUIDED VASCULAR ACCESS DEVICES

Fig. 5 is a table summarizing some of the features of the devices of this invention (e.g., catheters, stylets, guide wires) as shown in the following figures. In general, it may be desirable to place the sensor at or near the center of the vessel to, for example, avoid interference between the sensor and the vessel wall. In decatheter embodiments, this feature can be implemented as a basket around or near the sensor. Alternatively, the distal end of the catheter may be provided with a preformed bend or curve to push the sensor opposite the vessel wall. In stylet or guidewire embodiments, on the other hand, a J-shaped tip or hockey stick may serve this purpose.

Some embodiments make use of ultrasound-derived information to make it possible to direct a device within a blood vessel. This can be accomplished by integrated design features that enable steering along with a sensor or sensors that provide real-time feedback information indicating tip position within the vascular system.

An important design feature enables torque control. Guided vascular access devices equipped with acoustic sensors, including catheter devices and stylet / guidewires, can be constructed using high torque materials to allow precise control of the distal tip by rotating the catheter shaft or device near the insertion site. More particularly, one embodiment of a stylus (ie, Fig. 23A) may be inserted into the lumen of a catheter (Fig. 23B), whereby the stiffness of the stylet 2312 is used to transmit torque or otherwise manipulate the catheter. 2370 and provide steering control in response to the information provided by the system.

Another device design goal is to minimize device profile while maximizing sensor size. In catheter realization modes, this goal may be achieved by arranging the sensor in a recess formed at the distal end of the catheter.

In some embodiments, the locating device may be used solely to guide another device (such as a dispensing and therapy device) to a particular location in the vascular system. In other embodiments, however, locating devices may be integrated with therapy dispatching devices. In such embodiments, the catheter or other device may be provided with therapy delivery lumens in addition to the device locating elements. Alternatively, the catheter may be provided with slots, valves, ports, etc., for therapy dispatch fines. Groshong describes the use of closed-end catheter valves in US Patent 4,549,879 for two-way valve catheter. Some embodiments of the invention acquire directional data that can be used, for example, to determine the direction of blood flow. In such catheter embodiments, one or more sensors may be tip-mounted and forward-facing, laterally-mounted side-to-side, and / or rear-facing sensors. There may also be multiple sensors in one or more locations. Stylus and guidewire embodiments may also have sensors facing forward, backward, or in combination.

Some embodiments may provide features for maximizing the volume of sensor data acquisition. For ultrasound-based sensors, for example, the volume of data acquisition may be increased by expanding the beam to isolate a larger volume (via, for example, a divergent beam) and / or by collecting a larger volume by converging the beam. collection beam. Lenses and lens assemblies (e.g., acoustic lens assemblies, patterned epoxy lens assemblies, microlens arrayed, machined crystals may be used for such purpose.

Tracking devices can use a variety of sensors, shapes and materials, depending on the application. For example, the device may use one sensor, multiple sensors, rectangular sensors, round sensors etc. Suitable ultrasound-based sensor material includes piezoelectric crystals (such as quartz), galvanic ceramics (such as lead zirconate titanate), silicon, and galvanic films (such as PVDF). Lenses (eg convergent, divergent) may be made of polypoxy methacrylate (PMMA) and polycarbonate (PC) variable weight fraction epoxy reinforced, Araldite® (Gy508 / Hy956, Ciba), EPO-TEK®353 ND (Epoxy) Technology), or Rexolite® (Curbell Plastics). In some embodiments, the sensor may be made "non-discharging" (for example, without requiring discharge for the purpose of purifying air or other ultrasonic limiting material) by encapsulating the sensor in epoxy or other air-tight and transparent sealant. ultrasound. The casing may also be used to couple the sensor to the catheter or other device and may be formed in the form of a sensor lens. Emitition, the sealing material used to encapsulate the sensor in a soundproofing environment may be non-transparent to the acoustic energy generated by the sensor. Thus, in some embodiments, the material used to provide a sealed, air-tight environment for sensor operation may also act as an acoustic lens for the sensor (s) to be sealed.

Lens Arrangements

The use of an orderly array of tens of diameter microlenses instead of a single lens with a diameter of 1-2mm covering the entire crystal surface (see Fig. 17) is also revealed. An orderly arrangement of lenses will allow one to not only create a divergent beam (for example, defocused), but also direct the ultrasound energy generated by the piezoelectric crystal in different directions. Ordered microlens arrangements can be etched in fused silica.

MODEL SENSORS

In most cases, ultrasound sensors such as ultrasound crystals, for example, use acoustic lens assemblies coupled to a piezoelectric crystal (PZT). The use of laser micro-machining of the PZT element is revealed, producing a patterned crystal and thereby altering the acoustic wave (Fig. 14D).

EMCATETER-BASED GUIDED VASCULAR ACCESS DEVICES

Fig. 7 shows an embodiment of the invention. Four-sensor 715 (e.g. Doppler crystals) are provided at the distal end 713 of a catheter 712 as a commercially available catheter. Ocateter 712 has three other lumens 705 to be used for other purposes. A disadvantage of this configuration is that it reduces the number of lumens 705 available in an existing catheter. Sensors 715 communicate with the proximal end of catheter 712 via (not shown) wires passing through lumen 720. It should be appreciated that proper electrical wires and connections (not shown in many of the following figures) conventional to the ultrasound technique connect the sensors described herein to appropriate system components such that sensors can be operated to produce and / or receive acoustic waves.

Figs. 8A and 8B illustrate another possible embodiment of a catheter assembly with side-facing sensors. In this realization mode, sensors 615A, 815B, and 815C are built into the wall of catheter 810 on each side of 805 lumen. Wires (not shown) extending proximally from the sensors communicate with a forced patient control system to provide power, data acquisition, etc. . Sensors can be multiplexed to reduce the number of wires extending to the control system. In an alternative embodiment, one or more forward facing sensors may be added to the side sensors shown in Figs. 8A and B. A forward facing sensor may be used, for example, for speed detection using Doppler techniques, although side sensors may be used, for example, for speed detection using Doppler techniques, although side sensors for speed detection. wall using scan-A. In addition, inclined sensors may be used to provide blood velocity in both directions along the catheter axis.

Embodiments of the present invention also relate to the use of catheter-integrated Doppler sensors, so that sensors can monitor blood flow direction, i.e. in or opposite direction of the catheter, and detect Doppler flow patterns to determine location. of the Doppler sensor in the vascular system. Several types of Doppler technique can be used to achieve these goals, including continuous wave (CW) and pulsed (PW) Doppler. References to continuous wave directional Doppler serve as examples and should not be construed as limiting the invention. From a catheter set point of view, CW requires two transducer elements: one that transmits the ultrasound unit and one that receives it. One such embodiment of dispensers is illustrated in Fig. 8A. PW requires only one transducer element, but more electronic, so that the same element can be sequentially transmitted to transmit and receive the ultrasonic wave.

Figs. 9A-D show a decentralized recovery boiler for a catheter with locating devices according to this invention. In this embodiment, sensors 915A and 915R are arranged at the distal end 913 of a catheter 912. Expandable centering wires 930 (formed, for example, from a superelastic material, such as a Nitinol shape memory material, or a biocompatible plastic) they are arranged radially around the catheter 912. Centering wires 930 may also take the form of narrow strips or may be replaced by a balloon that may be selectively inflated to maintain centering. Selective balloon inflation allows it to be more inflated by centering a device on a larger vessel and less inflated to center the device within a smaller vessel. Whether strips, balloon or other inflatable element, centering elements 930 expand substantially uniformly around catheter 912 to hold the catheter approximately in the center of vessel 80. Fig. 9C shows the device in a small diameter vessel, and Fig. 9D shows the device in a larger diameter vessel, where 930 centering wires are most fully expanded. In this embodiment, centering yarns 930 are self-expanding. In alternate embodiments, the wires, strips, or inflatable centering element may be actuated by a user. Catheter 912 is also provided in this embodiment with a side discharge port 920 for providing therapy, as a pharmacological agent, via a lumen (not shown) within catheter 912 as is conventionally made with closed end catheters.

Figs. 10A-C show another feature of a catheter with locating devices according to the present invention for adapting the catheter for use in vessels of different size. In this embodiment mode, a sensor 1015A is disposed on the catheter side 1012, and a sensor 1015B is disposed on the distal end 1013 of the catheter. The distal end of catheter 1012 can be bent by the user as shown in Fig. 10A, using conventional catheter tip directing techniques. The amount of bending can be changed depending on how sensors 1015A and 1015B are being used and the size of the vessel as shown in Figs. 10B and 10C. Alternatively, catheter 1012 may have a preformed bend that the catheter assumes when inside a vessel, as shown in Fig. 10C. The preformed bend provides a centering feature by keeping the flow-oriented sensor 1015A within the vessel 82. Fig. 11A shows an embodiment of the invention in which a sensor 1115 is disposed in a recess 1112 of the elongate body 1112. The recess 1122 is within elongate body 1112 and bounded by surfaces 1128, 1129 and seal 1130. Angle O2 is formed by surface 1128 and surface 1129. Surface 1128 in recess 1122 deviates from the surface of catheter 1112 or other elongate body as indicated. Oi angle. The angle Oj indicates the sensor angle 1115 reacting to the catheter axis 1112. Oi angle variations are useful when using sensor 1115 for Doppler readings. One or more sensors 1115 may be positioned on surfaces 1128, 1129 and annuli 0] and O2 may be varied to pause and / or receive acoustic signals with the qualities and characteristics described above.

The recess 1122 may be loaded with a sealing material, a lens material or a sealing material having lens characteristics as indicated by reference numeral 1140/1130. An ultrasound transparent air-tight seal 1130 is provided over recess 1122 and sensor 1115. Sensor 1115 and its seal and / or lens is substantially approximately flush with the outer surface of catheter 1112 at this mode. The size of seal 1130 is not illustrated for scaling and should not have an edge against the elongate body on surface 1112 but would not be traumatic if it contacted a vessel wall.

Fig. 11B shows an embodiment in which sensor 1115 and its seal 1130 and / or lenses 1140 extend beyond the outer cylindrical surface of catheter 1112. Recess 1122 may be loaded with a characteristic sealing material, lens material or sealing material. as indicated by reference num. 1140 / 1130.A clear ultrasonic air-tight seal 1130 is provided over down 1122 and sensor 1115. Seal 1130 and / or recess loading1222 can also serve as a lens for sensor 1115. The size of seal 1130 and the size / shape of recess 1122 extending above the surface are not shown to scale and might not actually be as apparent as an edge over seal 1130 or swelling over the loaded portion in comparison. to the surface plane of the elongated body 1112. The sensor, seal / lens and sealing assembly are constructed to remain Typical is colocadosem contact with a vessel wall.

Fig. 12A shows an embodiment in which a sensor1215 (possibly covered by a lens 1230) is disposed at the distal end 1213 of a closed end catheter 1212. Slots 1250 allow substances to be dispatched through catheter 1212. Ports or valves may be sweaty in place of cracks. Slots 1250, other ports and valves, and further on the operation and use of closed-end catheters are further described by Groshong in US Patent 4,549,879. One or more additional sensors could be included on the closed end catheter 1212 as on the distal end 1213 or laterally mounted as described below with respect to Fig. 13C. Fig. 12B shows the addition of an atraumatic tip 1260 at the distal end of catheter 1213.

Fig. 13A shows an embodiment in which three sensors 1315A-C are disposed at the distal end 1313 of the catheter and a sensor 1315D is disposed over the side of the catheter. A 1340-shaped seal covers the 1315D sensor. Fig. 13B shows an embodiment with only two sensors 1315B and 1315F at the distal end of the catheter.

A lens / seal (not shown) may also be placed in Figs. 13A, 13B over the distal ends to seal and / or modify the acoustic waves generated by the sensors 1315A-F. In Fig. 13C, sensor 1315D is seated on an inclined surface 1328 and covered by a lens / seal 1340.

Figs. 14A-E show different sensor and lens arrangements.

In Figs. 14A-C, differently shaped lenses 1440A-C are illustrated covering a 1415 sensor. The shape of the 1440A-C lenses can be used to modify the acoustic wave transmitted or collected by the 1415 sensor to have the desired characteristics for performing ultrasound techniques here. described.

In Fig. 14D, the sensor surface 1415D itself has been altered to produce a patterned surface 1420. Patterned surfaces 1420 can be formed on the sensors using suitable modeling processes such as the use of laser micro-machining of a sensor made of zipper material. Due to the characteristics of the 1420 patterned surface, a 1415D activated sensor produces a divergent 93 beam as shown. In Fig. 14E, a plurality of lenses 1440E (such as fused desyllic lenses) having patterned surfaces 1472 cover sensor 1415E to provide a plurality of divergent beams 93.

Fig. 15 shows a stylus or other elongated body 1512

with sensors 1515A and 1515B at its distal end. Lenses 1540A and 1540B cover sensors 1515A and 1515B, respectively, having different shapes and providing different beam shapes for transmission or collection. In this embodiment, one sensor can be used as a transmitter (ie 1515A) and the other as a collector. (i.e. 1515B).

Fig. 16A shows a stylus or other elongate device 1612 with a distal end 1613 in which a seal 1630 covers sensor 1615. Seal 1630 may be formed of a suitable ultrasonic transparent material to provide an air-tight environment for alternatively, the 1630 seal may have acoustic beam changing properties so as to act as a lens in addition to providing an air-tight environment for the 1615 sensor. In contrast, the 1630 seal is separated from the 1640 lens in Fig. 16B. Lens 1640 is sized to conform to the size and surface of sensor 1615. As illustrated, seal 1630 covers the distal end of stylet 1613 and may be used to secure lens 1640 to sensor 1615 and both of these components to distal end 1613.

Fig. 17 shows a sensor 1715 to which an array of microlens 1740 has been coupled. The shape of the lens 1726 may provide a diverging (e.g., defocused) beam 93 and may direct the ultrasound energy generated by the sensor (such as a piezoelectric sensor) in different directions. The shape of the lens 1726 need not be the same as given by lens 1740 at all locations in the ordered arrangement. In contrast, in some embodiments, the shape, size and density of the microlenses 1740 will vary across the surface of the sensor 1715 to produce the desired ultrasound beam characteristics. The ordered array of microlenses may be formed of chemically etched fused silica, for example, or other suitable lens material as described herein or known in the art of ultrasound.

GUIDE-BASED VASCULAR ACCESS DEVICES GUIDE-BASED

Figs. 18A-C show the use of a locating device with a guidewire 1812. In Fig. 18A, the sensor 1815 is disposed distally 1813 of the guidewire 1812. The guidewire portion 1813 is folded substantially substantially in Ieo. The sensor 1815 is disposed on the concave side of the folded portion facing the proximal end of the guide wire 1812. When a sheath or other device 1870 is loaded onto the guide wire 1812, the sensor 1815 faces the device 1870 as shown in Fig. 18B. The J-shape of the guide wire 1812 also provides a centering feature within the vessel lumen 80, as shown in Fig. 18C. Techniques for Coupling Sensors to Guidewires and Directly Inserting them into the Bloodstream as disclosed by Millar in US5.046.497 for Structure for Coupling a Guidewire and Catheter and US4.966.148 to Assembly for Positioning Diagnostic Devices in a Bloody biological.

In Figs. 19A and Β, the sensor 1915 is disposed on the convex edge of the distal portion 1913 of the guidewire 1912 so as to face it opposite the sheath 1970 or other device carried over the guidewire. As in the embodiment of Fig. 18, the shape J-shape of the guidewire provides a centering feature for the device to keep the sensor out of the folded-up portion of guidewire 2013. J-shape 1913 of guidewire 1912 also provides a centering feature within vessel lumen 80, as shown in Fig. 19B. Figs. 21A and 2IB show an alternative to the realization modes of Figs. 20. In Figs. 21A and Β, the guide wire 2112 has a distal portion 2113 in the form of a hockey stick. In Fig. 21A, the sensor 2115 is disposed on a surface of the bent portion 2113 opposite to a proximal portion of the guide wire (i.e., the guide wire portion positioned before the bend of the guide wire), and in Fig. 21B, sensor 2115 is disposed on a surface of the folded portion 2113 of the guidewire facing the proximal portion of the guidewire. As in the embodiments of Fig. 20, the folded portion of the guidewire helps to center the device within the vessel to hold the sensor opposite the vessel wall. The guidewire can also be provided with an atraumatic point 2280.

Figs. 22A and B show a sheath 2270 for use when inserting the guidewire of Figs. 20 or 21. As shown in Fig. 22A. The 2270 sheath keeps the guidewire substantially straight for introduction into the vascular system 80. When the sheath is extracted from the guidewire (or when the guidewire is advanced beyond the sheath), the distal end 2213 of the guidewire 2212 assumes its pre-fold. -formed (shown here as the dehockey stick shape). A sensor 2215 is shown on the distally directed face of the guidewire. The guidewire may also be provided with an atraumatic tip 2280.

ESSENTILE-BASED GUIDED VASCULAR ACCESS DEVICES

Fig. 23A shows an embodiment in which a plurality of sensors 2315 are disposed on the distal end 2313 of a stylet 2312 or other elongate body. In this embodiment, sensors 2315 are arranged in two sensor areas 2318 and 2319. In an alternate embodiment, sensors in one sensor area operate as emitters and sensors in the other sensor area act as collectors. One seal, lens or The sealing lens may be used to cover one or more of the 2315 sensors in one sensor area, all sensors in one sensor area, or all sensors in both sensor ares. In other embodiments, more than two sensor areas are used. The number of detent 2315 on a sensor may vary depending on the function and location of the specific sensor area, such as tip mounted as shown, side mounted (ie, Figs. 13C, 11A, 11B) or angled (Figs. 8A, 6B) A 2390 wire or other electrical connection extends proximal to the sensors. As shown in Fig. 23Bm the stylet 2312 may be arranged in a lumen 2305 of a multi-lumen catheter 2370 for guide. As shown in Fig. 24, two guide sensors with distal sensors 2415 may be disposed in a catheter 2470. Sensors 2415 may also be covered by a seal, lens or sealing lens as described herein. In alternative embodiments, the guide rods may include one or more side sensors such as the arrangement shown in Fig. 13C which are used in conjunction with or in place of the distal end sensors illustrated 2415.

Fig. 24 illustrates an embodiment in which the vascular access device is a stylus with two sensors on the distal end. In one embodiment, a sensor is coupled to the distal end of a stylus used to navigate the PICC through the vascular system. . At the proximal end, a data acquisition unit acquires Doppler frequency changes, for example, directional continuous wave Doppler. A signal processing unit analyzes the Doppler frequency change, ie blood velocities, and determines the blood flow direction relative to the catheter tip. The signal processing unit is also responsible for identifying the unique flow pattern characteristic for the superior vena cava junction and the right atrium. The sensors may be a piezoelectric crystal, a piezoelectric ceramic, comprise silicon or a thin piezoelectric film. Ossensors can be made of the same or different materials.

As illustrated in Fig. 6, vascular access devices described herein may also be categorized as targetable or non-targetable. As illustrated in Fig. 6, a suitable conventional directional (i.e., catheter or guidewire based) system may be employed to provide directional control of the guided vascular access devices of the invention described herein. The result is an open loop feedback-based Ioop guide system. Similarly, Fig. 6 illustrates how a suitable conventional steering system of a guidewire-based steering system, when used to provide steering control of a guidewire-based guide vascular device, results in a Ioop vascular guide system. feedback loop. Steering ability can be provided in several ways. A guided vascular access device of the present invention may be modified to include and be controlled by the components of a conventional defo-guide guidance system catheter. Alternatively or additionally, a vascular access device of the present invention may be incorporated into the interventional or diagnostic medical device. Examples of catheter direction systems are described in the following patents relating to steerable catheters 7,037,290 to Gardeski et al. For Multi-lumen steerable catheter; 5,938,603, from Ponzi, for electromagnetic sensor steerable catheter; 6,866,677, to Douk et al., For Temporary Intraluminal Filter Guidewire and methods of use; 6,591,144, from Pigott, for Direction Catheter and methods for locating coronary sinus, and 5,803,083, from Bucket al., For Guide Catheter with ultrasound imaging capability. Examples of steerable control systems are described in the following patents: 6,500,130, to Kinsella et al., For steerable guide wire, 6,638,243, to Kupiecki, for balloon catheter with side clearance holes, and 6,973,352, to Tutsui , for pacemaker and heart rate sensing catheter and guide wire for implanting wires.

Figs. 6A and 6B show a steerable embodiment of a guided vascular access device of the present invention adapted for use with an oximeter catheter 6010 which may be used to practice the present invention. The 6010 catheter includes a 6020 directional cannula, including a 6021 blood contact sheath that is made of low thrombogenicity biocompatible polymers. One or more side sensors described herein may be placed along the length of cannula 6020 to aid in guiding. Preferably, encased in cannula 6021 of cannula 6020, there is a steering mechanism including a steerable 6024, and a blood feature sensor as a fiber optic oxygen sensor assembly 6028. The fiber optic oxygen sensor assembly 6028 and other sensors appropriate cardiac monitoring methods appropriate to the heart access methods described with respect to Figs. 46 and 47 and associated methods for guiding or accessing the left heart via the inventive methods of locating the coronary sinus. The electrical wires for all sensors, 6024 steerable guide, and 6028 fiber optic oxygen sensor assembly preferably run the full length of cannula 60 6020 to distal end 6032 and also extend from proximal end 6026 of cannula 6020. 6028 fiber-optic oxygen sensor could be replaced by another sensor appropriate to other blood characteristics that correlate with the sinuscoronary blood, such as pH or CO2 content.

6024 steerable guide preferably includes an outer tube

6025 and an inner wire 6027 passing from the distal end 6032 to the 6030 steering control module. 6034 finger grips and the 6030 control module thumb grip are reciprocally movable with respect to each other along the axis of the 6024 steerable guide. 6036 is attached to the outer tube 6025 of the guide 6024 and the finger grips 6034 are attached to the proximal end of the inner wire 6027. The distal end of the inner wire 6027 is attached to the distal end of the 6024 steerable guide tube 6024 in an axially offset manner as known. in technique. Alternatively, the outer tube 6025 may be disposed of and the inner wire 6027, in contrast, attached directly to the cannula 6021 of the cannula 6027. Pulling the finger grips 6034 toward the thumb grip 6036, the inner wire 6027 is pulled in, deflecting thereby, the distal end of the steerable guide 6024 and thus the sheath 6021 and cannula 6020 to one side. By a combination of distal end deflection of cannula 6020 via grips 6034 and 6036, and rotating the entire catheter 6010 about its longitudinal axis, similarly via grips 6034 and 6036; The distal end of catheter 6010 may be directed anywhere within a 360 degree range. Other targeting mechanisms known in the art may also be used. The user may apply steering controls based on the output of the processing system of the present invention.

A blood feature sensor uses fiber optics to sense oxygen content, but alternatively or additionally, pH or CO2 sensors can be used. The 6028 fiber optic assembly includes a pair of 6029 and 6031 optical fibers fitted to a 6033 tube. These fibers - along with electrical connections for the 6015 sensors - run the full length of the 6028 assembly and are connected at their proximal end to a 6038 photodetector optical module. , and on a processor and screen (modified to generate, collect and process the ultrasound data of the inventive system), respectively.

According to a well-known phenomenon, blood color is a function of the percentage of oxygen saturation in the blood. Consequently, the color of light absorbed by the blood, and hence the color of light reflected back to optic module 6038, is also a function of the oxygen content of the blood. The photodetector in optical module 6038 differentially responds to different wavelengths of light, and generates a signal indicating the wavelength of reflected light received via the fiber optic. The generated signal can be transmitted via appropriate conductors 6039 to a processor and display module 6041 which can process the signal and display the percentage of oxygen saturation in a form that is read directly by a person on a digital screen. Processor and display module 6041 also includes the components required for the operation of the sensors shown, as described herein. The oxygen content output, or other parameter measured here, may also be indicated as part of that presented to the user, as in Figs. 49. 50A and 50B.

The 6010 steerable oximetry catheter, which combines inventive ultrasound sensors described herein with an oxygen-sensitive 6028 fiber optic assembly with a steerable 6024 guidewire into a common 6020 cannula, provides a new, useful technique for localization of the sinus sensorineural . The oxygen content of the blood in the coronary sinus is known to be among the lowest in the human body. This phenomenon is explored by the 6010 steerable oximetry catheter, in cooperation with the dosing and processor capabilities of the present invention, to identify unique flow patterns and signatures to facilitate the localization of the coronary sinus. Monitoring oxygen content along with information of flow pattern and other blood characteristics in the vicinity of a distal end of catheter 6010 in real time as catheter 6010 and sensors6015 advance through the right atrium (initially located using the techniques of Figs 45, 46 and 47 ), the operator can know if the distal catheter end is in or deviating from a path approaching the sinus sinus. The system's detection of a standard flow signature, in conjunction with the percentage of perceived oxygen saturation that continues to fall as the 6010 catheter is advanced, leads the operator to know that the distal end of the catheter is getting closer to the sinus sinus. If oxygen saturation begins to rise or the detected flow patterns and parameters indicated by the 6015 sensors change as the catheter is advanced, then the operator knows that the catheter is forced stroke and he can correct the stroke using the catheter directionality feature. Indeed, the operator is seeking to detect single flow patterns and parameters of the coronary sinus in combination with the blood under oxygen that exists from the coronary sinus to the right atrium. As an iterative procedure, the operator can make use of the percentage oxygen desaturation being realized in real time along with the flow patterns and parameters detected to guide and adjust the catheter direction to find the coronary sinus. The above iterative procedure can be used to increase the blood flow information provided by the methods described herein and in addition present it to the user on an appropriate screen.

Fig. 6C is a side view of a multi / single beam ultrasound guide catheter of the present invention with an electrophysiological catheter within the guide catheter and two thumb sliders to guide the guide catheter. Fig. 6D is a side view of a multi / single beam ultrasound guide catheter of the present invention with an electrophysiological catheter within the guide catheter and four sliding lugs (only three are shown) to guide the guide catheter. A model use of such a device is the use of the sensors and methods described herein, for use as an identification of unique flow patterns to be used in locating an endocardial ablation site and then positioning an electrophysiological catheter to guide diagnostic and accessory ablation.

Guide catheter 6110 comprises three primary components. Guide catheter body 6111 defines a central lumen 6130 (shown and described with reference to Fig. 6D) within which a 6015 electrophysiological catheter is guided. One or more ultrasound sensors 6118 and side sensors 6117 are fixedly coupled to the distal end of the catheter body 6111. In turn, the guide catheter body 6111 is fixedly coupled to its proximal end on a hub 6113 by conventional means.

An outlet port 6114 is defined towards the distal end of the guide catheter body 6111 through which the electrophysiological catheter 6116 exits central lumen 6130. The electrophysiological catheter 6115 comprises an electrode tip 6116 at its distal end to map and / or remove endocardial tissue, and is mounted at its proximal end on a control handle 6119. Preferably, the electrophysiological catheter 6115 is steerable by longitudinal movement of the control handle 6119 relative to the body of the electrophysiological catheter 6115. Aberrant signals from the conductive path may be received from the lead tip 6116, and transmitted to a remote detector and presented via a molded electronic connect 6120. RF energy can be transmitted to the electrode tip 6116 via a remote RF source, also connected to the molded connector 6120. A model example of an electrophysiological catheter suitable for use with the present invention is a catheter of open, directional lumen as described in US Pat. No. 5,431,168 to Webster, Jr. for Open lumenable, steerable catheter manufactured by Cordis Webster, Inc. Baldwin Park Calif. However, many other electrophysiological catheters can be used without departing from the scope of the invention.

The guide catheter body 6111 may be any length suitable for intravascular insertion. In the described embodiment a length of about 10 cm is used. Similarly, outlet port 6114 may be of any appropriate size to allow an electrophysiological catheter to exit the guide catheter body 6111. In the described performance mode, a size of 0.04 + - 0.03 inches and the distance was used. between the distal edge of outlet port 6114 and the distal end of catheter tip 6112 is approximately 2.5 cm. One or more ultrasound sensors 6118, 6117 are fixedly coupled to the distal end of the guide catheter body 6111. Sensors 6118, 6117 emit and receive ultrasound as determined by the control system described herein in Figs. 25, 26 and 27, for example. In addition, other step configurations described herein may be employed to obtain additional flow information. The exact dimensions of the sensors 6118, 6117 are not critical and any suitable construction sensor, or described herein, may be employed. Preferably, the sensor is cylindrical with a rounded tip about 1 to 2 cm long and has an outer diameter of about 12 to 12.5 French to form a continuous outer surface with the guide catheter body 6111.

The guide catheter body 6111 comprises four main sections, as follows (from distal to proximal end): a main body 6127, a first transitional tip 6126, a second transatontal tip 6125, and the distal tip section of catheter 6112. Each of these four sections can have any appropriate construction and dimensions.

A braided wire sleeve 6134 also runs the length of the guide catheter body 611 but only until through the second transitional tip 6125, ending slightly near the end of the second transitional tip 6125 to form a junction section of the proximal tip of catheter 6128. In the mode In the described embodiment, the joint section width of the proximal tip of catheter 6128 is approximately 0.04 + -0.03 inches and the braided wire sleeve 6134 is preferably constructed of stainless steel.

A cross-sectional view of the guide catheter body 6111, taken along line 4-4 of Fig. 6C, is shown in Fig. 6E. With the exceptions indicated here, the construction of each of the four sections that comprise the guide catheter 6111 body are substantially similar and involve the following layers. The innermost layer is an inner liner 6132, preferably constructed of PTFE and defining a central lumen 6130 running longitudinally its entire length.

In the described embodiment, the central lumen 6139 has an internal diameter of about 0.110 inches. Preferably, the inner liner 6132 defines two longitudinal notches 6136, on their outer surface, on opposite sides of each other. A pair of small pull wire tubes 6133 are located in the notches 6136 to maintain their orientation. Preferably, the pull wire tubes 6133 are constructed of polyamide with an internal diameter of approximately 0.012 inches. Pull wires 6121 run axially within the pull wire tubes 6133. The 6121 pull wires (not shown for simplicity) have a diameter of about 0.012 inches (0.03 cm). The pull wires 6121 are constructed of 6150 stainless steel cable with a 6151 PTFE sleeve covering them to provide lubricity within the polyamide tubes 6133.

A layer 6135 of eight braided ribbon cables 6153 runs longitudinally along each side of the pull wire tubes 6133, and is arranged to surround the inner sheath 6132. In the described embodiment, the guide wires for sensors 6118, 6117 should be disposed within the stranded cable layer 6123 which may include bundled stranded cables bundled together with 6152 microcoaxial individual wires about 0.02mm thick. The braided wire sleeve 6134 correlates longitudinally with the pull wire tubes 6133 and the braided stranded cable layer 6135. Preferably, the braided wire sleeve is constructed of stainless steel. Finally, the outer sleeve 6127, described above, preferably constructed of nylon, surrounds the braided yarn sleeve layer 6134.

The tip of the catheter 6112 is steerable using the pair of pull wires 6121. To aid in guiding, each of the pull wires is connected to a 6170 thumb slide which is slidably mounted on the outer surface of the grip preferably of its distal end (Fig. 6C). The pair of thumb sliders are mounted side by side on handle 6173.

Sliding the thumb sliders toward the catheter in a proximal direction pulls the pull cord into which it is connected and causes the tip of catheter 6112 to deflect horizontally. The deflection is such that the tip of catheter 6112 becomes concave on the side of the pull fiode that was moved closer. Reverse deflection of the catheter tip occurs by sliding the opposite thumb slider closer to the guide catheter. Catheter tip deflection 6112 can be used to alter apposition of sensors 6117, 6118 by altering the divergent ultrasound beam produced to accurately characterize adjacent flow patterns. Bidirectional movement in a left-right horizontal plane is achieved using the 6170 thumb sliders that are attached to the 6121 pull wires. As described, the tip of catheter 6112 is capable of 10 to 4 ° free movement. In one embodiment, having a single pull string, only a single thumb slider is required.

Fig. 6E is a plan view of a steerable guide wire 6200 having side sensors 6215A, and forward-looking sensors 6215B, according to embodiments of the present invention. Fig. 6F is a planar view of a distal portion of a guidewire according to a model embodiment of the present invention. Guide wire 6200 includes a distal end 6206, a distal portion 6208, and a proximal end 6222. Guide wire 6200 also includes a shaft assembly 6220 having a distal end 6226 and a proximal end 6222. As shown in Fig. 6E, the assembly Shaft 6220 includes a coil 6230 defining a lumen 6224 and a wire 6240 disposed in the lumen 6224 of coil6230. A distal end 6236 of spool 6230 is fixed to a tip member 6250. Likewise, a distal end 6246 (not shown) of thread 6240 is attached to tip member 6250. Wire 6240 extends below one end. terminal 6232 of coil 6230 forming a terminal portion 6244 of wire 140, terminating at terminal end 142 of wire 140.

The yarn 6240 of the guidewire 6200 includes a curved portion 152 disposed near the distal end 6206 of the guidewire 6200. In the embodiment shown, the curved portion 6252 of yarn 6240 is shown in a substantially unsolicited position. In the shown embodiment, the coil 6230 is pressed into a substantially bent shape by the curved portion 6252 of the 6240 yarn. The curved portion 6252 of the 6240 yarn is requested to return to a generally curved shape after deflection. 6230, is formed by a plurality of turns 6254. The longitudinal axis of the coil 6230 is disposed along a generally curved path. Coil 6230 defines a plurality of gaps 6256 disposed between adjacent turns of coil 6230. Those skilled in the art will appreciate that curved portion 6252 may have any angle of curvature, depending on need.

Fig. 6G is a plan view of the guidewire 6200. In this embodiment mode, a plurality of grippers 6258 are disposed near a proximal portion 6234 of spool 6230. Also shown is a force F acting on the proximal portion 6244 of the wire. 6240. As previously described, curved rod 6252 of yarn 6240 is required to assume a generally curved shape. Applying force F to proximal portion 6244 of duct 6240 pushes turns 6254 of coil 6230 closer and force and presses wire 6240 to a substantially rectified state. When in use, for example, a physician may grasp the proximal portion 6234 of coil 6230 with the thumb and index finger of his left hand. Also, in this example, the physician could grasp the proximal portion 6244 of the 6240 wire with the thumb and index finger of the right hand. The physician could then force the proximal portion 6244 of the 6240 wire closer to the proximal portion 6234. of the coil 6230.

In one method, according to the present invention, guidewire 6200 may be inserted into a patient's vascular system, and forced through the vascular system, until the tip member 6250 of guidewire 6200 is near a desired target location, as determined by the use of inventive directional techniques described herein. As guidewire 6200 moves through a patient's vascular system, it may be necessary to "guide" the guidewire. For example, the distal end of the guidewire 6200 may reach a branch in the vascular system. The physician may direct the distal end of the guidewire to the desired branch of the vascular system, based on feedback provided by processing the acquired sensor data 6215A, 6215B. Curved portion 6208 of guidewire 6200 may facilitate the steering process Torsional forces may be applied to the proximal portion of guidewire 6200 to alter the angular orientation of the curved portion 6252 relative to the blood vessel. In this manner, the distal end of the guide wire 6200 may be directed to place the sensors 6215A, 6215B, in a different orientation, within a vessel, for the acquisition and processing of additional sensor data to assist in guiding the guide wire 6200. Once the 6200 guidewire is positioned within the vascular system, the proximal end 6202 of the 6200 guidewire may be inserted into a guidewire lumen of a catheter (not shown). The catheter tip may be advanced along the length of the catheter. guide wire until it reaches a desired target location. In this manner, guidewire 6200 may assist a physician in placing the distal tip of a catheter at a desired target location, in particular, target locations identified using the ultrasound signal processing techniques described herein. The term "yarn" as used to describe yarn 6240 and elsewhere in this application is not to be misunderstood as a limitation of yarn 6240 to elements having a circular cross section. Cross section of wire 6240 can have various shapes. For example, the cross section of wire 6240 could be rectangular, elliptical, etc. Similarly, the term "wire" as used in the description of wire 6240 should not be misunderstood as a limitation to metallic materials. In fact, the 6240 wire may comprise many metallic and non-metallic materials. Examples of metallic materials which may be suitable in some applications include stainless steel, tantalum and titanium. Wire 6240 may also include a nickel titanium alloy known in the middle as Nitinol. Nitinol is commercially available from Memory Technologies (Brookfield, Conn.), TiNi Alloy Company (San Leandro, Calif.), And Shape MemoryApplications (Sunnyvale, Calif.). Examples of non-metallic materials, which may be appropriate in some applications, can be found in the following list, which is not complete: polycarbonate, poly (L-lactide) (PLLA), poly (D, L-lactide) (PLA) , polyglycolide (PGA), poly (L-lectid-co-D, L-lactide (PLLA / PLA), poly (L-lactide-co-glycolide) (PLLA / PGA), poly (D, L-lactide-co glycolide (PLA / PGA), poly (glycolide-co-trimethylene carbonate) (PGA / PTMC), polyethylene oxide (PEO), polydioxanone (PDS), polycaprolactone (PCL), polyhydroxybutyrate (PHBT), poly ( phosgene), polyD, L-lactide-co-caprolactone) (PLA / PCL), poly (glycolide-co-prolactone) (PGA / PCL), polyanhydrides (PAN), poly (ortho esters), poly (phosphate ester) ), opli (amino acid), poly (hydroxybutyrate), polyacrylate, polyacrylamide, poly (hydroxyethyl methacrylate), polyurethane, polysiloxane and their copolymers. In addition, guide wire 6200 may also include a wire 6240 having tubular cross section. For example, wire 6240 may comprise Nitinol hypodermic tube.

PROCESSING SYSTEM Examples of ultrasound control systems are described in the following patents: related to ultrasound imaging, patents US 6,896,658 to Ji et al, para, Multi-modal and multi-simultaneous ultrasonic imaging track; 6,251,073 to Imran et al., For Miniaturized ultrasound method and apparatus; 5,492,125 to Kim et al. For Ultrasound Signal Apparatus; 6,561,979 to Wood et al. For Medical Diagnostic Ultrasound Method and System; and 5,477,858 to Norris et al. for Blood Flow / Tissue Ultrasound Imaging System; related to Doppler ultrasound, US 4,324,258 to Huebscher et al., for Ultrasonic Doppler Flowmeters; 4,143,650 for Hatke for Directional Doppler Ultrasound Systems for audio signal acquisition and method of using the same; 5,891,036 to Izumi for diagnostic Doppler wave ultrasound; US-related patents 5,220,924 for Franzin for Doppler-guided retrograde catheterization using a wire-guided transducer 6,704,590 for Haldeman for Doppler-guided catheter using sensed blood-disturbance levels; 5,311,871 for Yock Syringe with ultrasound transducer for directed flow cannulation of arteries and veins; 6,612,992 to Hossack et al. for medical diagnostic ultrasound catheter and method for determining positioning; related to the screening method, U.S. Patent 5,785,657 to Breyeret al., for Blood Flow Measurement Device; related to pressure assessment, US Patent 5,749,364 to Sliwa Jr. et al., for Method and apparatus for mapping pressure and tissue properties.

Fig. 25 shows a more detailed block diagram of

additional components within the data acquisition and control unit 150 and the signal processing unit 160 introduced in Fig. 2. As shown in Fig. 25, the data acquisition and control unit 150 includes a waveform synthesizer 2510 and a transmit / receive switch and a 2520 multiplexer.

The 2510 waveform synthesizer, as a programmable pulse frequency generator or the like, is used to generate electronic signals, such as electronic pulses in Fig. 32, which are used to guide ultrasound sensors 115. Electronic signals are individually delayed, since its sequence is programmed to generate the sequences shown in Fig. 32, depending on which processing mode is determined by the system control logic.

The output of the waveform synthesizer is coupled to a power amplifier included in the transmitter block 2520, such as a high speed FET power amplifier, or the like, where it is amplified and passed by a transmit / receive switch. The transmit / receive switch 2520 sends / receives signal data to and from the sensor (s) in the system and provides the acquired data to the signal processing unit components 160. The transmit / receive switch optionally includes a multiplexer configured to couple the signals. waveform generator signals to the desired sensor and the desired sensor to the corresponding signal processing path in block 160. Ultrasound sensor 115 generates a unique divergent ultrasound beam by transforming the electrical energy of the power amplifier into acoustic waves. mechanical frequencies between 5 and 15 MHZ.

Sensor 115 is configured to transmit an ultrasound beam to a material under investigation. In the material under investigation echoes are generated by the interaction between the divergent, unique ultrasound beam, objects scattered backwards, such as blood, and reflective objects such as vasosanguines and walls of the heart. Sensor 115 receives the generated echoes and produces corresponding electrical signals, transforming the high frequency double-wave mechanical wave into electrical energy. These electrical signals are received by the transmit / receive switch and multiplexed into the desired signal path by block 2520.

The signal processing unit 160 receives the electrical signals representing ultrasound echoes from the multiplexer 2520 and distributes them to a processing path according to the mode selected by logic control mode 2702. The processing path includes a Doppler speed estimator 2530 for provide blood velocity and direction information used in determining direction and positioning. The signal processing unit includes a 2540 target tracker to provide information on the movement of slow moving targets, including vessel walls and blood groups at low speeds. Signal processing unit 160 includes a target frame evaluator 2550 to determine if the sensor is in contact with the wall. The frame evaluator 2550. is also used to provide information on wall closeness, and to assess the internal diameter of the blood vessel. As indicated, outputs from the 2530 Doppler velocity assessor, 2540 target crosstalk and 2550 target structure evaluator, are all received in the pattern analysis block 2560. The pattern analysis block evaluates the blood pressure gradient from the velocity gradient and vessel internal diameter information, determines the blood flow pattern, and evaluates the signature pattern of an ultrasound. sound, an object of interest, including a location within the blood vessel.

Fig. 26 shows a flow chart 2600 showing one embodiment of a targeting algorithm implemented by the multi / single beam ultrasound system. First, at step 2605, you start a self test. If the sensor and system pass, the green LED flashes.

Next, in step 2610, the system acquires data from the sensors. As shown, it had to have one or more single beam sensors under control of the data acquisition and control unit. Next, in step 2615, calibrates and computes patterns / thresholds for direction identification. Next, in step 2620, calibrates and computes patterns / thresholds for direction identification. If necessary, it compares to a pre-stored database of flow patterns that identify certain locations in the vascular system. After this, in step 2625, it stores the defaults / thresholds.

Next, at step 2630, the system will provide an indication to the user to notify the user that the calibration has been done by changing the green LED to a solid green light.

After completing calibration, the next step 2635 is acquired from the sensor or sensors in the system. Acquired data is processed using one or more of the Doppler velocity evaluators, the target tracker, and the target structure and pressure estimator calculated as instructed by the control system logic.

Next - in step 2640. The acquired data is subjected to pattern analysis to determine if the sensor data contains a pattern that can be recognized by the system. If the result in step 2640 is NOT, indicating that a pattern cannot be recognized, then the system will stop step 2645 to compare the sensor data with the data provided by the target frame evaluator to determine if the sensor is against appears from the vase.

If the result of step 2650 is YES and the wall is detected by the system, the yellow LED will illuminate to notify the user that the sensor is against the wall. Next, the system returns to step 2635, and acquires data from the sensors.

If the result of step 2650 is NO, and neither the previous processing steps nor the wall pattern match, then the system was unable to determine the sensor location and the yellow LED will flash yellow to indicate to the user that the system was unable to determine the location of the sensor. sensor location. Next, the system returns to step 2635 and acquires sensor data. If the result in step 2640 is YES, indicating that a pattern in the sensor data can be recognized, then the system proceeds to step 2665 to compare sensor data with the pattern. If the result of the inquiry in step 2665 is YES, that the sensor data indicates that wrong direction of travel, then the user is notified by illuminating the red LED. After that, the system returns to step 2635 and acquires data from the sensor to determine if the wrong direction indication can be clarified.

If the result in step 2640 is NO, indicating that direction pattern matching indicates that the sensor is moving in the proper direction, then the green LED will be illuminated to notify that the current catheter advance direction is the correct catheter advance direction. .

The sensor data is then compared to the deposition pattern (step 2680). If the result of that comparison is NO, the catheter is not in position, then the system returns to processing step 2685 and acquires data from the sensors.

If the result of that comparison in step 2680 is YES, the catheter is in position, then the system continues to step 2690 and notifies the user that the sensor is in the proper position and illuminates the blue light.

Figure 27 illustrates a block diagram of a realization mode of a 2700 single beam ultrasound system. The system consists of a mode selector 2715 that allows selection of one of the following operating modes: Mode A or Scan-A, continuous Doppler waveform (CW) or pulsed waveform (PW), and target tracking or single tracking.25 Modes can be selected individually or in sequence by either of the sensors connected via the 2702 control logic. Waveform synthesizer generates excitation pulses for sensors according to the scheme or sequence programmed by the control logic 2702. The 2520 transmit / receive switch switches the electrical paths between the system and sensors between transmit and receive modes. The 2520 multiplexer multiplexes the system usage between multiple sensors. The 2720 mode selector selects the signal processing path as programmed by the 2702 control logic. Three signal processing paths are available that can be used independently or in any combination: 2730 Doppler processing for calculating blood speed and direction 2730, target tracking 2735 to calculate slow motion of blood and other targets of interest, eMode A and Scan-A 2740 for target structure calculation 2745. Pressure 2750 can be calculated using any of a number of conventional techniques where pressure is calculated using the information One such technique is described in US Patent 5,749,364, the entirety of which is incorporated herein by reference. The 2650 pattern recognition and analysis engine calculates blood flow patterns 2765, dealvo signatures 2775 and finally the location of the distal tip in the vasculature using 2770. Database information 2775 is used to compare detected patterns. A 2760 calibration block performs in-patient patient-specific system calibration. The self-optimizing block 2780 performs context-dependent adjustment of system settings. Control logic for mode selection 2702 selects the mode or operating sequence of the modes based on user input and current system settings.

The 2510 waveform synthesizer generates the excitation waveform for the sensors. The waveform depends on the operating mode: Scan-A, Doppler, tracking and can be selected according to desired mode. Any combination of operating modes can be selected at any given time. Figure 32 shows that η sensors can be triggered in real time, whereby each sensor is triggered as a result of operating modes. As illustrated in Figure 32, sensor A is first triggered by a pulse that periodically generates a Scan-A. In the preferred embodiment a scan-A is generated every 10 ms. If an additional sensor is present, the additional sensor can be immediately triggered with a Doppler pulse sequence triggered at a frequency called the pulse repetition frequency (PRF). In the preferred embodiment, the PRP is 40 kHz. If only one sensor is triggered in both scan-A and Doppler modes, the Doppler pulse sequence can be triggered only after a 1 / PRF delay after the A-scan pulse. After a delay of at least 1 / After the Doppler pulse has been triggered, the sensor can be fired again to obtain the tracking information. Tracking mode requires two pulses fired in sequence at different times in time. In the preferred derealization mode shown in Figure 32, the delay between the two pulse pulses is approximately 1 ms. After all modes have been triggered in sequence for one sensor, the following sensor can be excited in the same or different sequence. In addition, all sensors can be excited and the sequence starts again from the first sensor. Any combination of excitation pulses is possible between different modes and different sensors. For example, sensor 1 may be excited in tracking mode and sensor 2 may be excited in tracking mode immediately thereafter. In this sequence, angle independent velocity measurements can be made. In addition, examples of parametric waveform generation are given in the following patents, each of which is incorporated herein by reference in its entirety. See, U.S. Patent Nos. 6,896,658 to Ji et al for multi-mode and multi-band ultrasonic imaging and US 6,551,244 to Gee for the Parametric Transmission Waveform Generator for medical ultrasound.

The 2510 waveform synthesizer also allows coded excitation. The excitation encoded in Figure 33 provides increased penetration depth for a larger sample volume. It allows for better contrast resolution that helps tracking (correlation) algorithms with blood flow detection. Figure 33A illustrates a unit pulse waveform at operating frequency. In the preferred performance mode the preferred frequency is 10 MHz, 33B illustrates coded excitation. At the same operating frequency, a sequence of positive or negative polarity pulses is generated. In the preferred embodiment the sequence consists of 2 positive polarity pulses followed by a span followed by a positive and two negative polarity pulses. Phillips U.S. Patent No. 6,213,947 to the medical diagnostic ultrasonic imaging system using coded transmission pulses describes an alternative method of coded excitation.

The Transmit / Receive Switch and Multiplexer 2520 are of the conventional technique. This function block multiplexes the desinal path alternately for all connected sensors. In pulsed mode it also switches the signal path for the sensor between transmitting and receiving. Such functionality is described in U.S. Patent No. 6,896,658 to Ji et al. For multi-mode, multi-band ultrasonic imaging and is incorporated herein in its entirety by reference.

Figure 31 illustrates the specific properties of the sensor-generated ultrasound beam as a result of excitation according to the present invention. As illustrated in Figure 5, the sensor and elongated limb are optimized to generate the largest possible beam, ie the largest possible diameter in Figure 31. In order to maximize the volume of the target analyzed with a given beam, the extent of the volume is equally maximized. The target volume of interest is defined as the three dimensional regions encompassed by the beam geometry and contained in the acquisition window. The maximum sample volume depth extension or acquisition window extension is determined by two parameters: operating frequency and pulse repetition frequency. The operating frequency determines the depth of ultrasound penetration into the tissue. In a preferred embodiment, the operating frequency is approximately 10 MHz. This allows a maximum penetration depth of approximately 20 mm. At 20 MHz5 the penetration depth is only 3-5 mm, which is insufficient to analyze the flow vein in large veins of 10-20 mm internal diameter. The repetition pulse frequency in the preferred embodiment of the current invention is approximately 40 kHz. This allows the ultrasound wave to penetrate deep enough for venous flow between two pulses. It also allows you to calculate Doppler velocities relevant to venous flow. In arterial flow the pulse repetition rate (PRF) should be around 100 kHz in order to capture the high velocities of arterial flow. 100 kHz PRF, ie pulse repetition interval of 1 / PRF does not allow the ultrasound beam to travel deep enough between two pulses to generate a large enough sample volume.

The functionality of the 2735 Target Tracking block is also known as "Cross Correlation", "Auto Correlation", and "Correlation" methods. The proposed tracking algorithm is based on the idea of tracking a target in time, for example, a cell or blood group, and detecting its position at two different times in time. By determining the distance traveled by the target between the two time points, the velocity of target can be calculated. This concept is illustrated in Figure 28. Assume that at time ti the system receives ultrasound steels from the target volume and at time t2 receives different echoes from the same target volume. The system uses cross-correlation signal processing techniques to match specific echo patterns at time ticontra echo patterns at time t2. When patterns match, they are said to be correlated. Velocity calculation is another result available from cross-correlation analysis, because the analysis determines the distance between married patterns. Assuming that the matching patterns represent the same target, the estimated speed of that specific target can be calculated from the time difference and the distance traveled. The turbulence calculation refers to another result of the cross-correlation analysis where the amount by which an echo pattern has changed from one moment to the next. The more correlation there is, the more streamline the flow, because of the smaller changes between the moments. Menoscorrelation indicates more turbulent flow.

Figure 29 illustrates a preferred embodiment for method 2900. The signal from the sensor is input in real time through block 2905 containing a temporary data entry storage with memory, preferably a double ping pong temporary storage with a memory of at least two scans A. The received signal is processed by 2910 to remove noise and scaled back to a predetermined value to facilitate cross correlation computation. Block 2915 computes the cross-correlation function using a programmable window, as illustrated and described above in Figure 28. Block 2920 determines the characteristic point on the axis, that is, the maximum correlation point. Assuming that the speed of sound is approximately 1540 m / s in human tissue, including blood, the distances from Figure 28 corresponding to the maximum correlation delay can be calculated. Block 2930 calculates the target velocity from the ds value and from the dt delay between the two scans A under analysis. Decronometer block 2940 synchronizes cross-correlation computation with waveform synthesizer 2510 (Figure 27). The velocity calculation output is directed by 2950 to the pressure estimator block 2750 (Figure 27) and flow pattern estimator 2765 (Figure 27).

Unlike Doppler methods, which depend on the angle between the probe or sensor and blood flow, the tracking methods described here are angle independent. Independent tracing provides the ability to better detect locations in the vasculaturdependent than the relative tip position is relative to the hollow wall. Independent angle tracking also provides a technique for separating lower velocities from desired targets (ie, blood) from lower velocities from unwanted targets (ie vessel wall motion artifacts). Conventional Doppler techniques do not allow these separations or distinctions in low speed tracking. The inventive method angle independent tracking techniques rely on volumetric indications, not occasional indications, as used in Doppler processing. In other words, inventive method angle-independent tracking techniques provide information from a larger sample volume of the free-flowing blood flow from the sample volume size limits imposed by the Doppler processing methods.

Turning to Figure 27, the pressure estimator 2750 calculates the blood pressure gradient as the device with the sensor advances through the vasculature. Pressure is calculated from the blood velocity gradient as determined equally by Doppler or target tracking methods and from a calculation of the internal diameter of the blood vessel. In one embodiment, the blood internal diameter is also retrieved from a database based on the relative location of the sensor in the vasculature. In another realization mode, one of the sensors perpendicular to the direction of the device advance is used in mode A to calculate the proximity of the vessel wall and the vessel inner diameter. Pressure can also be calculated using any of a number of conventional techniques, where pressure is calculated using velocity information. One such technique is described in US Patent 5,749,364 to Sliwa Jr. et al. for method and apparatus for mapping pressure and fabric properties. An advantage of using the sensors of the present invention to obtain / measure pressure is the avoidance of the conventional pressure calculation technique which relies on injection of contrast medium.

Continuing in Figure 27, Doppler shift estimator2725 calculates Doppler shift as described in Figure 30. Speed and direction estimator 2730 uses Doppler shift to calculate velocity and spectral energy. Speed and spectral energy are then used by the pressure estimator 2750 to calculate the pressure gradients and the flow pattern estimator 2765 to determine the flow pattern and its trends. A signal from the ultrasound frequency is transmitted into the blood vessels. Let this frequency component be given by F. In the preferred embodiment of this invention. fO is approximately 10MHz. The retrodiffused echo from the blood vessels contains the frequency component exchanged for an amount directly proportional to the blood velocity. If the change in frequency is given by Af, and the corresponding velocity of blood flow by v, then Af = k * v, where k is a constant. Thus, the back diffused signal contains frequency component (f0 ± Δί). The sign of exchange is determined by the direction of blood flow. In a continuous wave ultrasound signal, the change in frequency is not due to only one blood velocity component. Instead, it is a contribution of a number of speed components. Thus, instead of a unit frequency exchange, there is a frequency band in the exchanged component. The signal is detected in the time domain and the Fourier transform is computed to generate the frequency domain signal. The indicative frequency exchange of blood velocities can be analyzed in the time domain using the zero crossing counter technique. In the frequency domain, the frequency shift can be calculated using Fourier analysis. In the embodiment illustrated in Figure 30, the waveform synthesizer 2510 provides the excitation pulses for one or more of the sensors described herein. And for the mixer 3015 through a 90 degree phase detour block 3005. The set mixer 3010, the mixer 3015 and the "90 ° shift" block 3005 provide a quadrature demodulation of the received signal. The demodulated quadrature signals correspond to the direct (moving away from a sensor) and inverse (toward a sensor) speeds. Phase detectors compute the phase shift in these two signals that is indicative of blood velocity. Mixer outputs 3010 and 3015 go to a high filter optimized to remove "clutter" from the signal. In this example, the disorder is defined as low speed / high intensity movements, for example, the movement of a vessel wall. Low speed / high intensity motions interfere with accurate Doppler algorithm processing and are therefore removed. For adaptive disorder removal, the self-correlator (block 3025) can be used. During adaptive disorder removal, the auto-correlator processes the acquired data using a self-correlation function to determine if the disorder pattern is not present. If processing of data acquired using an auto-correlation function determines that the disorder is present (ie, oblique 3030 is YES), then the disorder filter is turned on and the circuit repeats until the disorder is reduced below a certain level. threshold. In this section, the signal and auto-correlation coefficients are additionally passed to the 2730 speed and detection estimator (Figure 27). The 2730 speed and detection estimator calculates Doppler frequency and spectral energy from the clutter-free generated signal and by target tracking estimator 2735.

Clutter removal removes low speed / high intensity information so as not to decrease the accuracy of Doppler measurements. However, low speed / high intensity information often includes data useful in detecting other targets of interest, including blood vessel walls. The proximity of the vessel wall to a sensor or device being guided in the vasculature should be known. One of the techniques used in the inventive system is to use two sensors for the acquisition of data from blood flow. In one embodiment of the present invention, the sensors are mounted on a vascular access device to optimize the data to be acquired by that sensor. In the event that velocity data is optimized, one or more forward or angled sensors are triggered in Doppler mode to provide velocity information. In the event that wall position / distance data is optimized, one or more side-facing or angled sensors are triggered in scan-A mode to provide information about proximity to the vessel wall. In another preferred embodiment, a sensor is triggered in a sequence of modes: a) in Doppler mode to provide speed and direction information and b) in rest-A mode to provide information about wall proximity, ie whether the sensor is near the vase wall. In one embodiment, the sensor is a tip mounted sensor (e.g., Figures 13A, 13B, 7, 8A, 23A and 24). In another embodiment, the sensor is a laterally mounted sensor (e.g., Figures 13C, 1AA, or 11B).

In addition to the pulsed wave mode described above (PW), the Doppler shift estimator and speed and direction estimators can be programmed to work in continuous wave (CW) Doppler mode. As is conventional in CW mode processing, two sensors are used. One sensor is continuously triggered to transmit ultrasound energy and the other is continuously receiving ultrasound echoes. Guided vascular access device embodiments illustrated in Figures 15, 9A, 13A, 13B, 24, 23A may be configured to operate under the CW designating sensor / sensors to transmit and other sensor / sensors to receive. It should be appreciated that other unitary sensor realization modes illustrated herein may be modified to include additional dedicated transmit or receive sensors. In addition, it should be appreciated that in the embodied guided vascular accessory device embodiments in which a unitary sensor is shown, it may be replaced by two sensors for CW mode operation.

Turning to Figure 27, A-mode or A-mode scan block 2740 receives and processes echo amplitudes from the target of interest in a conventional manner. By analyzing A-scan patterns, a target structure estimator (block 2745) provides information about the vessel wall, for example, the proximity of vessel wall to a sensor. This case can be seen in Figure 35 when sensor 110 is in position 2 and the scan-A signal in the illustrative waveform increases. This A-scan processing is especially necessary because Doppler processing (i.e. the clutter filter described in Figure 30) removes strong echoes from targets that move slowly like the vessel wall. The ultrasound processing techniques of the present invention advantageously use scan-A in sync and in combination with Doppler to optimize data acquisition and processing of the multi-unit beam ultrasound system here for blood flow velocities. drops found in the venous system. In this way, Doppler processing is optimized for low speeds through the clutter filter and scan-A is optimized for detecting the presence of strong echo vessel wall and slow motion.

As illustrated in Figure 27, the pattern analysis block 2650 processes inputs from speed and direction estimator 2730, correlator and target tracking estimator 2735, pressure estimator 2750, and target frame estimator 2745. Result of pattern analysis operations is used to provide information about the location of a guided vascular access device (block 2770). The result of processing by location estimator 2770 is used to control device status indicator lights (green, red, blue, and yellow etc) as needed for a specific user interface (eg Figures 4, 34-40, 49 , 50A, and 50B) or audio output (that is, 4901 speakers in Figure 49). 2650 Pattern Analysis provides real-time correlation of multiple sources for data acquisition and multidimensional pattern recognition. The functions performed in the 2650 pattern analysis can be modified to provide the location information and signature patterns 4945, 4935 illustrated in the graphical user interface 4900 (Figure 49). Additionally, the functions performed in the 2650 pattern analysis can be modified to remove the unwanted artifacts, so that the target signal signatures can be reliably determined. Examples of signal artifacts that may be removed by functions performed in pattern analysis 2650 include, by way of example and not limitation, respiratory movement artifact and velocity artifacts produced by manually advancing a bloodstream guided vascular access device.

The 2765 flow pattern estimator uses the velocity and pressure calculations to determine the temporal blood flow patterns: velocity profile, direction, energy spectrum. He maintains a temporary history store for these values for at least 100 heartbeats. It computes statistical averages of flow parameters over history temporary storage and computes the Fourier Transform to provide the energy spectrum for velocity data. In one embodiment, Fourier Transformation is computed as the Fast Fourier Transformation (FFT) algorithm. The results of the flow pattern calculations are Figures 34 - 48. For example, the graph "1" of Figure 34 shows the distribution of blood flow velocity as a function of time in the basilic vein calculated using Doppler signals or the blood flow method. target. Graph "1" in Figure 34 shows the same information for the brachial artery. In another example in Figure 36, the spectral energy of velocities away from the transducer (sensor) and towards the transducer (sensor) is illustrated. It is important to note, however, that Figures34-38 show simplified graphs of speed and energy for illustration purposes and are not intended to represent actual processed data.

Target Signature Estimator 2775 combines flow patterns and target frame information to determine a three-dimensional signature of an anatomical target. For example, Figure 35 shows a situation in which the elongated sensor member faces the vessel wall. The velocity curve shows an unexpected drop from a flow that could be predicted in the basilic vein "1" for lack of clear velocity information "2". This transition could have several causes. Looking at the A-scan pattern one can recognize a transition from blood (low reflectance) "1" to a target with high reflectance "2" that is likely a vessel wall. In addition, target tracking information can be used to verify that the target calculated as the vasose wall moves slowly. As an additional example of multidimensional target signature calculation, Grunwald describes methods for recognizing physiological structures based on statistical signatures using Grunwald US Patent 6,120,445 for the method and apparatus for adaptive cross-sectional area computation of IVUS objects using their signatures. Statistics.

The location estimator 2770 compares the estimated target signature with a database of signatures or guidelines to decalculate the location within the vessel. For example, the delocalization estimator 2770 is used to determine if, when a guided vascular access device moves, the device moves in the same direction or direction opposite the main blood stream flow in the vessel. After that, the user is notified about the result of the location calculation. It is important to note that the user also has direct access to flow patterns and A-scan information equally over a dedicated display (see Figure 49) or by switching a monitor to display flow patterns and A-scan information. Thus, the user must make the final determination regarding the direction actions to be taken based on the information provided by the system. In another example, the estimator 2770 detects the target signature corresponding to the lower third of the vena cava (i.e. Figures 38 and 53). Providing this information to the user, the system helps to position the sensor and catheter in the desired location. Figure 38 shows the flow patterns that can be used in one embodiment to calculate that the disnositivn has reached the SVC lower ground and turn the blue light back on. Subscription Database 2755 is used to compare the target signature estimator against the signatures in a database to identify the target. In another embodiment, the data bank stores anatomical decision criteria, thresholds, and statistical decision execution to provide target identification. Database and decision execution can be used independently. When used in combination, the information provided is correlated for safer target identification.

Calibration block 2760 serves to dynamically adapt system settings for each patient. This component is required to provide information about flow patterns in relation to the patient under examination. In this context, calibration means the determination of the velocities and blood flow patterns at the access point or immediately behind it, ie at a known point in the vasculature. These standards include, but are not limited to: average velocity, spectral velocities, velocity profile. velocity during a heart cycle, velocities and rates of forward and reverse flow etc. In addition, to determine the speed parameters at the access point, the calibration algorithm can compare and adjust these parameters against a bank of values and standards. Information about the relationship between access point patterns and endpoint patterns can be retrieved from the database.

The self-optimizing block 2780 is for automatic adjustment of system settings in order to optimize system operation. In one embodiment, the following parameters are optimized: 1) Dynamic variation for scan-A; 2) Disorder filter interruption frequencies; 3) Sample volume size to optimize speed information. Suitable self-optimization methods are described in US patents 6,733,454 of Bakircioglu et al. for the automatic optimization methods and systems for Doppler and 6,542,626 ultrasound imaging from Brouwer et al. for the apparatus method for adapting imaging system operation based on the depixel intensity histogram.

Figures 34-48 provide numerous specific examples of the multi-unit beam ultrasound system and the techniques for using it which are described herein can be used as an endovascular ejaculate access system. As will be appreciated by those skilled in the art, waveforms are simplified merely as an example of time-compressed composite waveforms for illustration purposes. The endovascular access and guide system includes an elongate flexible member adapted and configured to access a patient's vasculature as described above with respect to Figures 7-24.

In the following Figures, the methods described for navigating and locating structures within the vasculature will be described with reference to a guided endovascular access device 110. The guided endovascular access device 110 may be adapted to deliver therapy to the patient and / or to provide intravenous access. for another device. Device 110 may be a catheter, guidewire or stylus.

Guided endovascular access device 110 includes one or more sensors which may have an associated divergent lens disposed at a distal end thereof. One or more sensors are configured to provide non-imaging in vivo ultrasound information of the patient's venous vasculature into which the guided vascular endovascular access device 110 has been inserted. A diverging lens may be associated with the sensor or a plurality of lenses may be associated with the sensor. Additionally, a sensor sensor attachment mechanism may also be provided for removably detaching the sensor from the guided endovascular access device 110, while the guided endovascular access device 110 remains in the patient vasculature.

There is also a processor configured to receive and process non-imaging in vivo ultrasound information from the patient's venous vasculature provided by the sensor and to provide position information relative to the distal end position and / or sensor location over the guided endovascular access device. 110 within the patient's vasculature. The processor is further configured to process non-imaging live imaging ultrasound information from the patient's vasculature system to indicate the input information movement of the endovascular access device 110 in a desired direction within the patient's vasculature. Additionally, the processor is further configured to process non-imaging in vivo ultrasound information from the patient's vasculature based on a parameter selected from a group consisting of: a venous blood flow direction, a blood flow velocity venous, a venous blood flow signature pattern, a pressure signature pattern, A-scan information, and a preferred non-random flow direction. In each figure, a device progress or position indicator 50 acts as an output device adapted to output position information and other indicators from the processor. The progress indicator or device position 50 is illustrated with the appropriate light setting or the appropriate light setting color is shown in the figures.

More specifically, Figures 34-48 detail the methods for positioning an instrument in the venous system of a body by accessing the venous system of the body to position an instrument in the warm venous system. The instrument then transmits an ultrasound signal to the venous system of the body. In some embodiments, the instrument transmits a mode A ultrasound signal into the body venous system. In other embodiments, the instrument transmits a non-imaging cross-correlation sound signal within the venous system of the body. Thereafter, the sensor or another sensor is used to receive an ultrasound signal reflected from the vasculature. In some embodiments, the ultrasound signal reflected from the vasculature indicates flow rates between 2 and 20 cm / s. The reflected ultrasound signal is processed to determine a flow pattern within the vasculature. The given flow pattern may be in one direction toward or a direction away from the instrument. Next, the flow pattern determined within the vasculature can be used to advance the instrument within the vasculature. Additionally or alternatively, the flow pattern determined within the vasculature may be evaluated for the presence of a signal indicating a specific blood flow pattern.

Figures 34 to 39 will be used to describe how vascular access systems and techniques can be applied to gain access to the central venous system. In this example, the intention is to enter the venous system into the basilic vein and advance device 110 to a position 1/3 of the superior vena cava, as shown in Figure 38. This portion of a person's venous system includes the cephalic vein 8, the basilic vein 6, jugular veins 10, brachiocephalic (unnamed) 12, superior vena cava14 and inferior vena cava 16. Two features of the heart 20 are also illustrated in this view: the tricuspid valve 24 and the right atrium 22.

When guided endovascular access device 110 is first introduced into the vasculature, it may not be visible if the device has accessed a vein or artery. The waveform associated with '1' indicates a pulsatile flow that includes the flow away from and towards the sensor over device 110. The device status indicator 50 illuminates a red light to indicate that the sensor is detecting a flow pattern of the sensor. signature that is not in the desired direction. The system indicates a red light because the specified access method for this example is intended to guide device access along an antegrade venous outflow path to provide central venous access. The 1 'wavy shape clearly indicates that the sensor is not positioned correctly within the venous system.

Thereafter, device 110 is removed from the brachial artery and successively inserted into the basilic vein 6. The waveform associated with 1 indicates a nonpulsatile low-velocity flow away from the sensor. Device status indicator 50 illuminates a green light to indicate that the sensor is detecting a flow pattern and / or signature that is in a desired direction. The system has indicated that the sensor is in the desired position because the sensor is detecting flow patterns that indicate a position within the venous system with the flow going away from the sensor which also indicates that the sensor is correctly positioned for the desired anterograde motion toward the SVC.

After device 110 has been appropriately inserted into a person's venous system, data acquisition, signal processing techniques, and techniques described above in Figures 26, 27, 29, and 30 will collect patient-specific data for processing and write as part of a client-specific database as well as for use in the signature database. Acquisition of patient sensor data provides real-time in vivo system calibration for patient dependent processing. Depending on the specific circumstances of a particular patient, the system may, for example, assess the inlet blood pressure, velocity, peak velocity, and other factors. Additionally, patient sensor data will be processed through the processor to store data related to the processing of non-imaging ultrasound information in vivo from the patient vasculature system based on a parameter selected from a group consisting of: one direction venous blood flow rate, a venous blood flow rate, a venous blood signature pattern, a pressure signature pattern, A-scan information, and a preferred non-random flow direction. As discussed above with respect to Figures 26, 27, 29, and 30, these patient-specific factors relate to all system parameters and data subsequent to all values and data for this patient.

Turning now to Figure 35, the user will advance the device 110 through the vasculature, the basilic vein in this example, while monitoring the device status indicator 50. While the device status indicator 50 shows a "green light", the device is being moved toward desired. This means that signals received and processed by the system detect flow patterns and received signatures that indicate appropriate device movement / position. A green light indication will remain on as the device advances from 1 to log then contact the vessel wall at 2.

Figure 35 also illustrates the scan-A and Doppler and non-Doppler velocity waveforms for positions 1 and 2. The waveforms for position 1 indicate movement within the vessel in the desired direction: a constant velocity flow away sensor and a low A-scan waveform. In contrast, waveforms for position 2 indicate the position of the device against the wall (ie, high rest-A waveform) and low velocity flow away from the sensor and indications of the flow towards the sensor (ie , the slightly negative waveform). Thus, Figure 35 indicates sensor 110 in a condition that will generate a yellow system output on device status indicator 50. A yellow system output occurs when οε data acquired from the sensor does not contain recognizable standard or data acquired from The sensors do not provide any meaningful information from which any device position information can be derived.

As illustrated in Figure 36, the user maneuvered the device 110 to clear the yellow indication by moving the device to the indicated position. The action taken by the user restores the appropriate device movement within the vasculature. The green device status indicator 50 and the waveforms in Figure 36 all indicate that device 110 is advancing in the desired direction in position 3.

Figure 37 and associated waveforms indicate the result of advancing the device into jugular 10. Since the flow of blood in the internal jugular is toward the heart, current placement of the device produces waveforms from the sensors that clearly indicate that The device is not in the desired location within the vasculature. Suitably, the device status indicator 50 indicates a red light. As illustrated, when the device is within the jugular device 110 is immediately placed into a flow towards the heart (here also toward the sensor). Thus, the waveforms indicate a higher energy return directed toward the sensor as well as higher speeds toward the sensor than away from the sensor.

Figure 38 and associated waveforms correspond to the numbered position locators indicated in the patient vasculature illustration. The color of device status indicator 50 is indicated along the waveform corresponding to the signals received when device 110 is placed in that position finder. Waveforms and indication from the device status indicator 50 illustrate how the system can differentiate between the various different flow situations found within the vasculature.

The position indicator 4 of device 110 is advancing through the superior vena cava 14 in the desired direction so that the device status indicator 50 indicates green. The illustrative waveform shows the recognizable non-pulsatile unidirectional flow indicative of the venous system.

As device 110 travels along the SVC, sensors begin to detect the presence of venous flow coming towards the sensors from the inferior vena cava 16. As the device advances further, the signal from the IVC will grow and the sensors will they will also begin to detect the target signature or single-stream nonpulsatile bi-directional flow generated by the confluence of venous flows within the veiacava. As a result of placing sensors in this location, the reflected ultrasound signal processing from those sensors can be used to determine the position of the sensors or an instrument attached to the sensors with respect to the cavo-atrial junction. In addition, in this example, the flow path must have the rest of the sensors within the antegrade flow. In this example, anterograde flow means that when the device follows a path like this, the sensors predominantly detect flow away from the sensors and toward the heart (ie, an indication for this setting). Once the device advances past the right atrium 22 and into the inferior vena cava 16, the predominant flow is now towards the sensor causing the system to produce a device status indicator 50 that indicates red (ie, positions 6 and 8).

It should be appreciated that the method of detecting a flow sequence may also be used to determine the position of the device within the vasculature. For example, a pattern indicating a non-pulsatile unidirectional flowover pattern (i.e., position 4), then a non-pulsatile blue bidirectional flow pattern (i.e., position 5) and then with a device move forward - not backward, a strong non-pulsatile unidirectional red-flow pattern (ie, position 8) could be used to indicate the appropriate path for a user wishing to access the superior vena cava 16. The pulsatile bidirectional atrial and right ventricular flow can also be used. directed by the system. The unique pulsatile bidirectional flow pattern present when sensors are placed in position 7 can also be detected by the system and used to provide access to the vasculature.

Figure 39 illustrates the unique waveforms generated with base sensor inputs when the device is placed in the indication positions. When the device is placed at position 5 in the lower 1/3 target region of the superior vena cava 14, the status indicator 50 turns blue and waveforms indicate non-pulsatile bidirectional energy. In contrast, when device 110 is placed within the right ventricle, the waveforms generated from the sensor data indicate a clear and strong pulsatile bidirectional flow pattern.

Figure 40 illustrates the waveforms and direction indicator for a sensor intended to advance to the superior vena cava 14, which instead reaches the inferior vena cava 16. Note that the waveforms show that when the sensor is in position 8 The energy away from the sensor is low, while the energy towards the sensor is much higher. These waveforms clearly indicate that the system has detected the flow direction as opposed to the desired flow direction. As a result, the status indicator turns red when the device is in position 8.

Figures 43A and B will be used to describe a single parameter for the multiple unit beam ultrasound systems of the present invention. Figure 43A illustrates the typical velocity waveform for an ultrasound system having an operating frequency of 20 MHz and a pulse repetition frequency of 100 kHz. An arterial peak velocity of 40 cm / second is indicated using a fluxu puisátii standard. Figure 43B illustrates that same high speed signal when received by our system operating at an operating frequency that is metadata to that of arterial ultrasound systems (ie 10 MHz) and a pulse repetition frequency that is only 40% of the frequency. pulse repetition (ie only 40 kHz). Remember that in a multi-unit beam ultrasound system configured to operate at low speed, large volume venous system sample environment where flow velocity ranges from 2 to 15 cm / second, a flow rate of 40 cm / second is not can completely characterized by the system as in Figure 43A. Thus, the slower system characteristics of our system interrupt the high end of the velocity curve, as indicated at A, ie at approximately 20 cm / second. When that interrupt speed is finally recorded by our system, it shows as a negative (ie speed reading below 0). Or, in other words, as a 20 cm / second flow in the opposite direction. This phenomenon is referred to as altered blood flow. By inducing high velocity changes, our system converts high velocities into low opposite direction speeds, ie translates speed information into flow direction information. This ability of the system is used to identify arterial or heart chamber flow, although all parameters are optimized to detect venous flow. In this way, the system can reliably identify transitions between venous and arterial or heart flows using the velocity information that characterizes the main blood stream.

Figure 44 illustrates an energy versus frequency curve900. Curve 900 indicates the energy curve for the pulsatile flow measured within the arteries of the heart. According to this invention the variation of energy spectrum values is divided into two regions. The lower 10-20% of energy represents non-preferential velocities in bloodstream. In contrast, the upper 80-90% of the energy represents the preferred velocities, that is, the non-random movements in the bloodstream, in this invention only the non-random preferential velocities are analyzed. A threshold is set for the energy spectrum at 10-20% of the peak amplitude. Speeds with a low spectral energy of the threshold are not considered for the analysis. Only speeds with a spectral energy above the threshold contribute to the signature patterns. For example, velocities illustrated by curve 902 representing random turbulence in a typical arterial flow are excluded from the analysis as being non-preferential and therefore irrelevant.

As a result of altering arterial flow alone or in combination with the removal of random turbulent flow, the multiple-unit beam ultrasound systems of the present invention may be used to detect changes in flow structures and patterns within the heart and surrounding vessels. Compared to prior art methods using random flow turbulence indicators, such as in Haldeman's US 6,704,590 patent for the Doppler steering catheter using sensed blood levels, the method presented in this invention provides a low frequency, low frequency identification method. more reliable and accurate speed of transitions between flow in the arteries or chambers of the heart and blood flow in the veins. The waveform illustrated in Figure 45 illustrates how the system can detect the transition from venous flow to arterial flow change as device 110 moves from the upper vein (i.e. venous flow) into right atrium 22 where the change begins. . In addition, the waveforms in Figure 46 illustrate representative signals detected by the system as device 110 is positioned in the right atrium. Because the system of the invention can be optimized to detect slowly moving objects that are typically filtered out of arterial ultrasound and imaging systems, tricuspid valve operation is readily detected by the system as indicated by the waveforms. As shown, our system converts the high velocities detected in a flux direction detection using the induced signal change. Similarly, this allows years for the system to convert high-speed signals to directional information.

Figure 47 illustrates a signature pattern sequence that can be used to reliably and accurately identify a pathway from the superior vena cava to the coronary cavity. Similar to the sequence described about where the system detects the transition from one distinct flow regime (one-way venous flow) to another (two-way cavo-atrial junction flow), the embodiments of the present invention can be used to detect the transition from one to another. It returns to venous flow after passing through an indication of atrial flow, eg through a cardiac chamber. The system's ability to detect such pattern changes will enable the devices and sensors of the present invention to identify, locate, and access venous flows entering the left atrium. In the example of Figure 47, pattern transitions from venous to altered and back to venous flow can be used to detect venous flow from the coronary cavity. Similarly, this technique can be used to identify one or more pulmonary veins or other venous flows into the left atrium. As discussed above, the sensor and tab access devices described above with respect to Figures 7-24 may be configured to mimic the expected anatomical and flow patterns or signatures to be generated by a right-hand sensor and consequently positioned.

TREATMENT OF VENOUS DISEASE

In the case of varicose vein treatment, a therapy catheter (ie, adapted to deliver laser, RF, or any other energy treatment for vein treatment) is positioned precisely at the pho-femoral junction (SFJ). The position of the catheter within the vein can be determined according to the present invention using the Doppler effect and the difference in blood flow patterns between the grandesafena vein (GSV) and the common femoral vein (CFV). For example, in the common femoral vein, blood flow changes more dramatically with breathing than in the great saphenous vein.

Figure 48 illustrates a guided vascular access device positioned at the saphenofemoral junction (SFJ). Also illustrated are anatomical landmarks that can be used for intravascular positioning of a venous catheter in the SFJ where many of the superficial veins appear together before joining the common femoral vein (CFV). The blood flow at this junction is controlled by a one-way valve that is designed to direct blood internally and upward, helping it return toward the heart. If this valve fails to function properly, part of the blood is able to flow back to the leg, increasing pressure on the superficial veins and their branches. The great saphenous vein (GSV) is one of the main superficial veins in the thigh. Extra force is forced into it by a valve leak in the SFJ, the vein stretches and the additional valves inside it become distorted and begin to leak. The blood is then able to flow further in the wrong direction, eventually filling and distending more and more ramifications, giving the appearance of varicose veins in the thigh and calf.

In the case of varicose vein treatment, a therapeutic catheter (i.e. a catheter adapted to deliver laser, RF, and any other type of energy for vein treatment) must be positioned precisely on the FSJ. The position of the catheter within the vein may be determined according to the present invention.

In case of SFJ detection, the deposition detection algorithm identifies the difference between the flow patterns in the GSV and the common vein. GSV blood flow is usually antegrade to the heart in GSV reflux patients when they are lying on their backs, which would be the case during a venous ablation procedure. And when the calf is tightened and then released that the blood flow will reverse for a brief instant - usually 1 to 4 seconds - as the blood distally invests in the GSV to fill the empty veins below. This maneuver can be performed during catheter placement with the patient in the inverted Trendelenberg position to help define FFS apposition.

In CFV the flow pattern also changes more dramatically with breathing. The CFV algorithm has a component that is capable of changing the Doppler signal due to the movement of blood vessels resulting from respiration. In addition, if the valve fails to function properly, part of the blood is able to flow back down to the leg, increasing pressure on the superficial veins and their ramifications. Blood flow in a diseased patient shows more reverse flow components in GSV compared to CFV. In the SFJ Duplex Scanning, the red color shows the forward flow in the CVF, and the blue color represents the inverse flow in the long saphenous vein. (Caution is important here as mild reflux is often commonly seen in the external distal and common femoral iliac veins). The intervention catheter is positioned in the GSV before the SFJ. The catheter point is located in the main blood stream of the CFV. The present invention discriminates between the two positions using Doppler signal analysis and flow pattern discrimination.

Once the appropriate sensor is placed in a position to properly detect venous flow in the diseased vein, then the detailed procedure above can be performed while the system monitors the flow performance characteristics of the diseased vein and vein. When blood flows away from the transducer in more turbulent patterns. In the femoral vein, blood flows toward the catheter in a stable flowomal pattern and with additional components due to breathing movements. Thus, embodiments of the system of the invention may be used to detect differences in flow patterns or flow signatures or other properties between the healthy vein and the diseased vein. As previously mentioned, the method also applies to the junction of the smaller saphenous vein and popliteal vein behind the knee and may also apply to identify the junction of a perforating calf vein and a superficial vein or a perforating vein and a deep tibial vein.

The detection of transition region flow patterns is based on the recognition of the characteristic flow signatures of the regions, for example, mean velocity, velocity spectrum, and ratios between forward and reverse flow, as well as changes in time. The inventive concept described herein of using physiological signatures or identifiers to detect specific locations in the vasculature from within the blood vessel can also be applied to other functional measurements other than Doppler velocity, for example, depression and temperature profiles. In such cases, appropriate pressure and temperature sensors would be used. As described herein, the processing and operation techniques of the multi-unit beam ultrasound system can be used to identify and discriminate the relative variation of pressure profiles at various locations in the vasculature. However, it has not been attempted, however, to date, to use such variations in order to identify the location in the vasculature as considered by the embodiments of the present invention.

In additional alternative embodiments, a method is provided for positioning an instrument in the vasculature of a body by processing a reflected ultrasound signal to determine the presence of a signal indicating a position where there are two or more vessel junctions. This method can be practiced in any of a variety of vascular junctions, both in the venous and arterial vasculature. An example deposition in which two or more vessels join occurs where the two or more vessels include an upper vena cava and an inferior vena cava. A second position example in which two or more vessels join occurs where the two or more vessels include an inferior vena cava and a renal vein. A third example of a position in which two or more vessels join occurs where the two more vessels include a right common iliac vein and a common left iliac vein. A fourth example of a position in which two or more vessels join together occurs where the two or more vessels include an external iliac vein and an internal iliac vein. A fifth example of a position in which two or more vessels join occurs where the two or more vessels include a right boar and a right brachiocephalic vein. A sixth exemplary position in which two or more vessels join occurs where the two or more vessels include an superior vena cava and an aziga vein. A seventh example of a position in which two or more vessels join occurs where the two or more vessels include a common femoral vein and a large saphenous vein. An eighth example of a position in which one or more vessels join occurs where the two or more vessels include a superficial femoral vein and a deep femoral vein. A ninth example of a position in which two or more vessels join occurs where the two or more vessels include a popliteal vein and a smaller saphenous vein. A tenth example of a position in which two or more vessels join occurs where the two or more vessels include a perforating vein and a superficial uveia. An eleventh example of a position in which two or more vessels join occurs where the two or more vessels include a perforating vein and a deep tibial vein. A twelfth example deposition in which two or more vessels join occurs where the two or more vessels include a large saphenous vein and a varicose vein. A tenth example of a position in which two or more vessels join occurs where two or more vessels include a jugular vein and a subclavian vein. A fourteenth example of a position in which two or more vessels join occurs where the two or more vessels include a cephalic vein and an axillary vein.

In one aspect the multiple-unit beam ultrasound system described herein is an intravenous access and guidance system having an elongate flexible member that is adapted and configured to access a patient's venous vasculature. One or more sensors are arranged around the elongate flexible member at various locations, such as the distal end, along the sides or in recesses formed in the lateral wall and in other configurations as described herein. These sensors are configured to provide non-imaging ultrasound information to invade the patient's venous vasculature. In addition, a processor configured to receive and process ultrasound information not based on in vivo imaging of the patient's venous vasculature provided by one or more sensors and to provide position information regarding the distal end position of the elongate flexible member within the vasculature. venous patient. Advantageously, the sensor, sensors and / or two or more additional sensors are attached to the elongate flexible member in an arrangement that burns an endovascular joint. There is also an output device adapted to output position information from the processor and to relate it, if desired, to the imitated endovascular junction. Sensors may also be arranged to mimic other measurable or detectable features or parameters within the vasculature. In specific embodiments, the sensors are arranged over the elongate body to mimic one or more of the fourteen position examples in which two or more vessels join.

The ability of the system of the present invention to recognize varying flow patterns within the vasculature can be used in a wide variety of situations. Embodiments of the present invention may be used to locate and identify single or signatures of the venous system where the detectable flow pattern provides accurate information about the position of the sensor or device within the venous system. As already discussed, the present inventive multiple unit defect ultrasound system can identify a central accession pathway through the superior vena cava. In the illustrative examples of Figures 41 and 42, the system may also be used to identify other venous landmarks as well.

Embodiments of the present invention may also be used to detect, locate and guide devices within the venous system portions shown in Figures 41 and 42. Taken together, these figures illustrate the ability of systems to detect and identify at least three other unique or signature patterns. within the vasculature. First, as indicated at position 1, a device 110 placed at position 1 can be used to detect the convergence of flows from the iliac veins 26 into the unitary flow of the superior vena cava 28. This flow pattern can be detected by the methods described herein to indicate similarly, the convergent bilateral flows from the renal veins 18 into the inferior vena cava 16 (position 2) can also be detected by the system. As indicated by the waveforms for position 3, the system can also detect the transition from the directional flow within the inferior vena cava to the bidirectional signature flow associated with the right atrium and the confluence of the superior and inferior vena cava. Thus, the system is capable of identify unique specific flow patterns and then relate the location of those specific anatomical reference point flow patterns as junctions between specific veins.

It should be appreciated that the configurations of the guided vascular access devices 110 described above in Figures 7-24 may have one or more sensors positioned over the device to detect an expected signature flow. For example, if the intended use of the system were to provide access and guidance to a healthcare provider attempting to place a filter within the inferior vena cava 16 higher than the renal veins 18, then a device 110 having a pair of laterally directed sensors ( ie at the 3 o'clock and 9 o'clock positions) would be able to detect unique or signature flow patterns when the sensors were properly positioned to detect those flow patterns. This way, when the system detects that signature pattern, the user could be notified and then the advanced device needed to reach the desired position superior to the renal veins (ie 1.5 cm superior to the renal veins). Of course, the position of the renal veins 18 could also be used to provide therapy or access to the renal veins 18. It should be appreciated that this general example applies to other regions of the vasculature, as well as where sensor placement over the device is selected to increase The probability of the sensor detecting a desired flow rate or other target vascular parameter later. In another illustrative example, a configured vascular access device for detecting the junction between the femoral veins and the iliac veins could have a combination of forward and posterior angled sensors to optimize the detection of that junction. Posterior sensors imitating the expected angle between the iliac veins 26 and inferior vena cava 28. Posterior and advanced in this example are, of course, relative to placement of the device within the flow vein. Here, the terms reflect traveling devices and sensors as indicated in Figures 42 and 42.

The above description relates to the use of sensors to mimic junctions or other detectable system parameters of venous vasculature. It should be appreciated that the invention is not limited and that the concept of sensor placement to mimic vasculature can also be applied equally to arterial vasculature.

Figure 49 illustrates a procedure-specific user interface 4900. The procedure-specific user interface 4900 is a hand-held electronic interface, PDA, or other suitable device that can graphically progress the progression of a guided vascular device along a desired path. The 4900 procedure-specific user interface includes the 4930, 4935 dials. Optionally, the 4900 procedure-specific user interface includes the 4901 and 4902 speakers. The 4930 display is configured to illustrate the progress of a guided vascular access device from the insertion point to a desired dispatch point. A plurality of path progress indicators 4905-4925 are arranged along the desired path. As shown in dial 4930, a display may also include an image 4940 that is specifically designed to show the expected vessel path path to be encountered by a particular device during a specific use. As shown in the 4935 display, a display may also be designed to show real-time system output based on data acquired from the sensors as shown in the waveforms in image 4945. Display 4930 and the plurality of path progress indicators 4905 The associated parameters can be configured to illustrate the progress of a guided vascular access device from an insertion point to a desired delivery point. In one embodiment, the target dispatch point includes those specific portions of the above described vasculature or venous system. Alternatively or in addition, one or more such plurality of pathway progress indicators 4905-4925 may be used to also include data received and analyzed from a sensor or sensors intended to mimic a portion of the vasculature described herein. In specific embodiments, the display 4930 and the associated plurality of pathway progress indicators 4905-4925 may be configured to illustrate the progress of a vascular access device guided from an insertion point to one or more of the fourteen position examples where two or more vessels come together. Additionally or alternatively, the sensors positioned on the guided vascular access device which are represented by the path progress indicators 4905-4925 are positioned on the vascular access device to mimic one or more of the fourteen examples of positions in which four or more vessels join.

The 4901 speakers can be configured to provide audible indication to the user that the device under the user's direction is following the desired path. The sounds played may correspond to the indicator lights described elsewhere in this application. Audible indication can also be as simple as a monotonic sound when the device is advancing properly and a stereo or other tone to indicate when the device is no longer following the indicated path. The right audio channel can provide an audible indication of Doppler frequencies and blood velocities away from the sensor, and the left audio channel can provide an indication of Doppler frequencies and blood velocities toward the sensor. In this way, the right audio channel and the green LED provide the indication that the device is following the desired path while the left audio channel and the red LED provide the indication that the device is on the wrong path.

Based on the signal processing results, the procedure-specific user interface 4900 indicates to the user catheter placement or catheter tip placement in the vascular tree. In a simple embodiment, colored lights may be used to indicate apposition of the catheter tip, for example, a green light may indicate blood flow away from the catheter, meaning that the catheter is pushed rightly toward the heart. A red light can indicate the flow of blood toward the catheter, meaning that the catheter is pushed the wrong way away from the heart. A blue light may indicate that a blood flow pattern has been detected that is indicative of the proximity of the junction between the vena cava and the right atrium.

For example, when a guided vascular access device is intended to be guided to the lower third of the SVC, then a specific dial may be provided which may be used to indicate the likely course of direction from a basilic vein entry to the SVC, as illustrated in Figure 4 (see image 4940). In a realization mode, position indicators 4905-4925 are LEDs and dial 4930 is a flat crimping to hold a static figure appearing as picture 4940 to which the LEDs are attached and visible to the user. It should be appreciated that other specific vasculature paths may also be indicated on a display as part of a specific 4900 user interface. Specific path applications are as varied as the procedures performed on or in the vasculature. LED indicators can also be used to provide other processed signal outputs from the system as well as including identifying a feature or portion of a vessel wall (i.e. identifying a stenosed portion of a vessel) or a specific identifiable anatomical reference point. , like a heart valve. It should be appreciated that the specific 4900 user interface could be configured to provide a display or image indicating a suitable path from an access point to a treatment site. Additionally, the display or image indicating a suitable path may be equipped to provide any form of user perceivable indication of the guided vascular access device movement according to the appropriate path.

Figures 50A and 50B illustrate variations on device progress indicator 50. The device progress indicator 50 configuration in Figure 50A has 4 lights 52, each with an individual colored color 53. The color indicators are associated with the described status indicators. on here. The device indicator configuration 50 illustrated in Figure 50B includes a unit light 54 and a multicolored lens 54 to provide device status indication. Lights 52, 54 may also be fiber optics, LEDs, or any suitable light source for visual indication of device progress.

As illustrated in Figures 51 and 52, the system components described above and also illustrated in Figure 2 may be communicating via conventional wired connections (Figure 51) or using a wireless connection (Figure 52). In one embodiment, the entire system is contained in a sterile single use package.

In another alternative embodiment, the components of the multiple unit beam ultrasound system described herein are divided into two parts. One part is a reusable user interface having processing system and user interface functionality. The other part is a single use guided vascular access device. The reusable user interface is maintained by a private healthcare provider or as part of the equipment provided and maintained in an operating room or treatment area. Communication between the reusable user interface and the single use guided vascular access device can be provided using conventional wired and wireless techniques. Wireless technology, such as the so-called Bluetooth technology, can also be used to communicate information between the components of the multi-unit beam ultrasound system described herein. In one embodiment, a wireless communication link is provided to enable communication between a grouping of disposable components on one side and reusable components on the other side. The disposable eye may, for example, include a vascular access device described herein (including one or more sensors), a 5220 data acquisition and control unit for controlling the high voltage high frequency signal required to drive the ultrasound sensor and The Cl5230 connector used to communicate low throughput information via a wireless Bluetooth channel to the reusable side. The reusable side consists of the 5240 Bluetooth connector that communicates with its counterpart5230, the 5250 standard processing and analysis unit, and the 5260 god interface.

Bluetooth is a low cost flexible wireless platform for short distance communication (<~ 10 meters). The cost of a Bluetooth radio chip has fallen by $ 20 and is now about $ 5. Bluetooth uses Gaussian frequency switching (GFSK) to switch data to frequencies around 2.4 GHz. Data is transmitted at 1 Mbps. For safety and noise reduction benefits, a Bluetooth transmitter employs frequency hopping switching channels up to 1600 times per second. Bluetooth is capable of point-to-point or point-to-point communication. This flexibility allows the Bluetoothser to be used in a wide variety of applications. Because power consumption is always a concern for mobile devices, Bluetooth has three power classes that can be used depending on how far apart the communicating devices are from each other. In the coming years, the use of Bluetooth is expected to grow significantly. The Bluetooth consortium is currently writing the specifications for Bluetooth2.0. Bluetooth 2.0 is designed to complement existing Bluetooth devices and will offer data rates of up to 12Mbps.

In one embodiment, the database used to store blood flow and other signature patterns is contained in the processing block. In this case, the defaults are stored for the duration of a single procedure. In particular, the calibration patterns stored at the beginning of the procedure are important in signal grading throughout the procedure. In another realization mode, the signature database is stored in the UI in instant memory. In yet another embodiment, the UI may communicate through conventional communication methods, such as Internet or LAN, with any relevant database.

Figure 51 shows a disposable steering system with all components connected to the sensor elongate member and packed in the same sterile package as the elongate member 5110. In this embodiment, the system is battery operated, the data acquisition unit 5120 is integrated within an application-specific integrated circuit (ASIC) together with 5130 processing algorithms. In another embodiment, the processing algorithms are programmed within a field programmable gate arrangement (FPGA). A DSP (signal processor) core digital) is integrated within a PFGA to provide a flexible processing environment. The 5140 sanctuary interface consists of a light enclosure of approximately 200 g and a small size of approximately 3x3x1 cm with a multi-color LED. The enclosure also contains the 5120 data acquisition and control unit and the 5130 processing unit. The multi-unit beam powered system requirements set forth in this invention are modest because it uses one or a few ultrasound beams to a depth. maximum penetration length of 15 mm. The size of the ultrasound sensor is small, the operating frequency is low, the cycle is low, and the electronics including the wireless device are integrated and have low power requirements. For all these reasons, the disposable system can be battery operated. In quantities of this type of product described herein designed to be sold on the market of several hundred million per year, the cost of goods becomes reasonably low for a disposable device.

Figure 53 will be used to illustrate the location sensing capabilities of the present invention that can be used to determine if a device has shifted from the position in which it was originally installed. The ability to determine if catheter-point migration has occurred is an important clinical benefit of the present invention.

For simplicity of illustration, the catheter tip is shown by device 110. Device 110 is in communication with the processing system described herein, an appropriate connector is inserted into connector 5310 to control the sensors in device 110. First, use the instrument to determine a location for holding a device 110 within the vasculature of a body. This determined position becomes the baseline or comparison for the value to assess whether the tip migration has occurred. As shown, the device 110 is in the SVC and is attached to the body holding the adhesive crimping 5305. The adhesive crimping 5305 secures the device 110 to the body to hold the device in the location determined by the instrument during catheter placement. Wherever the position of the catheter tip (here, sensor 110) is checked, the sensor is reconnected to the system via connector 5310. Once the sensors in device 110 are in communication with the processing system, then the system will operate. the sensors to acquire and process the data to then calculate device apposition. Then the system can determine if the device is in the location determined by the instrument by comparing the calculated position of the device to the location determined by the instrument.

According to one embodiment of the present invention, there is provided a method for positioning an instrument in the vasculature of a body using the instrument, determining a location for securing a device within the vasculature of a body; and securing the device to the body to keep the device in the location determined by the instrument.

After some time has elapsed (as it is common for patients who use catheters for an extended period of time) the instrument can be used to calculate the current position of the device. Then, using the original known position and the determined current position, the system can determine if the device has moved from the original position.

While preferred embodiments of the present invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes and substitutions will now occur to those skilled in the art without departing from the invention. It is to be understood that various alternatives to the embodiments of the invention described herein may be employed in the practice of the invention. It is intended that the following claims define the scope of the invention and that the methods and structures within the scope of these claims and their equivalents are covered accordingly.

Claims (55)

1. Intravenous access and guidance system, characterized in that it comprises: an elongated flexible limb adapted and configured to access a patient's venous vasculature, a sensor disposed at a distal end of the elongated flexible member configured to provide unsubstantiated ultrasound information. in vivo imaging of the patient's venous vasculature: a processor configured to receive and process non-imaging in vivo ultrasound information of the patient's intravenous vasculature provided by the sensor and to provide position information regarding the distal end position of the elongate limb within of the patient's venous vasculature; It is an output device adapted to output position information from the processor. Intravenous access and guidance system according to claim 1, characterized in that the elongate flexible member comprises a catheter. Intravenous access and guidance system according to claim 1, characterized in that the flexible elongate member comprises a guidewire. Intravenous access and guidance system according to claim 1, characterized in that the flexible elongate member comprises a stylet. Intravenous access and guidance system according to claim 1, characterized in that the flexible elongate limb is adapted to deliver therapy to the patient. Intravenous access and guidance system according to claim 1, characterized in that the flexible elongate member is adapted to provide intravenous access to another device. Intravenous access and guidance system according to claim 1, further comprising a sensor attachment mechanism adapted to removably attach the sensor from the elongate flexible member while the elongate flexible member remains in the patient's vasculature. Intravenous access and guidance system according to claim 1, characterized in that the processor is additionally configured to process non-imaging in vivo ultrasound information from the patient's vasculature system provided by the sensor to indicate in the output information. the proximity of the sensor to a structure within the patient's vasculature. Intravenous access and guidance system according to claim 1, characterized in that the processor is further configured to process non-imaging ultrasound information from the patient's vasculature system to indicate limb movement in the output information. stretched in a desired direction within the patient's vasculature. An intravenous access and guidance system according to claim 1, characterized in that the processor is further configured to process non-imaging ultrasound information from the patient's vasculature system based on a parameter selected from a group consisting of: a venous blood flow direction, a venous blood flow rate, a venous blood flow signature pattern, a pressure signature pattern, mode A information, and a nonrandom preferential flow direction. An intravenous access and guidance system according to claim 1, further comprising a divergent lens associated with the sensor. An intravenous access and guidance system according to claim 1, further comprising a plurality of lenses associated with the sensor. Intravenous access and guidance system according to claim 11, characterized in that the diverging lens is adapted to attach the sensor to the elongate flexible member. Intravenous access and guidance system according to claim 1, characterized in that the sensor is a first sensor adapted to transmit an ultrasound signal, the system further comprising a second sensor adapted to receive non-ultrasound based information. image in vivo. An intravenous access and guidance system according to claim 1, further comprising a sensor drive mechanism adapted to drive the sensor in a plurality of ultrasound transmission modes. Intravenous access and guidance system according to claim 1, characterized in that the sensor is a first sensor, the system further comprising a second sensor having a distal end of the elongate flexible member configured to provide non-ultrasound-based ultrasound information. in vivo imaging of the patient's vasculaturavenous to the processor. An intravenous access and guidance system according to claim 1, characterized in that it further comprises a centering element adapted to substantially center the distal end of the elongate limb within a vessel. An intravenous access and guidance system according to claim 1, further comprising two or more sensors wherein the sensor and two or more additional sensors are attached to the elongate flexible member in an arrangement mimicking the endovascular junction. An intravenous access and guidance system according to claim 1, further comprising a driving element for directing the device tip in response to feedback information derived from the acquired data. An intravenous access and guidance system according to claim 1, further comprising a torque control element for directing the device tip in response to feedback information derived from the acquired data. Endovascular access and guidance system, characterized in that it comprises: an elongate flexible member adapted and configured to access a patient's vasculature, a sensor and an associated divergent lens arranged at a distal end of the elongate flexible member and configured to provide ultra-ultra information. non-imaging in vivo imaging of the patient's vasculaturvena; a processor configured to receive and process non-imaging in vivo imaging of the patient's vasculaturosa provided by the sensor and to provide position information regarding the distal end position of the patient. elongated flexible limb within the patient's venous vasculature; It is an output device adapted to output position information from the processor. Endovascular access and guidance system according to claim 21, characterized in that the flexible elongate member comprises a catheter. Endovascular access and guidance system according to claim 21, characterized in that the flexible elongate member comprises a guidewire. Endovascular access and guidance system according to claim 21, characterized in that the flexible elongate member comprises a stylet. Endovascular access and guidance system according to claim 21, characterized in that the flexible elongate member is adapted to deliver a therapy to the patient. Endovascular access and guidance system according to claim 21, characterized in that the flexible elongate member is adapted to provide endovascular access for another device. Endovascular access and guidance system according to claim 21, further comprising a sensor attachment mechanism adapted to removably attach the sensor from the elongate flexible member while the elongate flexible member remains in the patient's vasculature. Endovascular guidance and access system according to claim 21, characterized in that the processor is further configured to process non-imaging in vivo ultrasound information from the patient's vasculature system provided by the sensor to indicate in the output information. the proximity of the sensor to a structure within the patient's vasculature. Endovascular access and guidance system according to claim 21, characterized in that the processor is further configured to process non-imaging ultrasound information from the patient's vasculature system to indicate limb movement in the output information. stretched in a desired direction within the patient's vasculature. Endovascular guidance and access system according to claim 21, characterized in that the processor is additionally configured to process non-imaging ultrasound information from the patient's vasculature system to indicate the proximity of the sensor to the output information. to a structure within the patient's vasculature. An endovascular guidance and access system according to claim 21, characterized in that the processor is further configured to process non-imaging ultrasound information from the patient's vasculature system based on a parameter selected from a group consisting of: a blood flow direction, a blood flow rate, a blood flow signature pattern, a pressure signature pattern, mode A information, and a preferred nonrandom flow direction. Endovascular access and guidance system according to claim 21, characterized in that the divergent lens is adapted to attach the sensor to the elongate flexible member. Endovascular access and guidance system according to claim 21, characterized in that the sensor is a first sensor adapted to transmit an ultrasound signal, the system further comprising a second sensor adapted to receive non-ultrasound based information. image in vivo. The endovascular guidance and access system according to claim 21, characterized in that the sensor is a first sensor adapted to receive non-imaging ultrasound information in vivo, the system further comprising a second sensor adapted to transmit a signal from ultrasound. Endovascular access and guidance system according to claim 21, further comprising a sensor drive mechanism adapted to drive the sensor in a plurality of ultrasound transmission modes. An endovascular access and guidance system according to claim 21, characterized in that the sensor is a first sensor, the system further comprising a second sensor disposed at the distal end of the elongate flexible member and configured to provide non-ultrasound based information. in the image I invented the patient's venous vasculature to the processor. An endovascular access and guidance system according to claim 21, further comprising a centering element adapted to substantially center the distal end of the elongate member within a vessel. Endovascular access and guidance system according to claim 21, further comprising a driving element for directing the device tip in response to feedback information derived from the acquired data. Endovascular access and guidance system according to claim 21, further comprising a torque control element for directing the device tip in response to feedback information derived from the acquired data. Endovascular access and guidance system according to claim 21, further comprising a plurality of lenses associated with the sensor. 41. Ultrasound sensor assembly, characterized by the fact that it comprises: an ultrasound sensor; An air-tight, ultrasound-transparent seal encapsulates at least one side of the ultrasound sensor. Sensor assembly according to claim 41, characterized in that the airtight transparent air-tight seal is formed in an acoustic lens. Sensor assembly according to claim 42, characterized in that the acoustic lens is formed to diffuse a beam generated by the ultrasound sensor. Sensor assembly according to claim 42, characterized in that the lens is made of epoxy. 45. Ultrasound sensor assembly according to claim 41, characterized in that the ultrasound sensor is formed from a piezoelectric crystal. 46. Ultrasound sensor assembly according to claim 41, characterized in that the ultrasound sensor is formed from a piezoelectric ceramic. 47. Ultrasound sensor assembly according to claim 41, characterized in that the ultrasound sensor is formed from silicone. 48. Ultrasound sensor assembly according to claim 41, characterized in that the ultrasound sensor comprises a thin piezoelectric film. 49. Ultrasound sensor assembly according to claim 41, characterized in that the ultrasound sensor comprises a plurality of micro-lenses. Sensor assembly according to claim 41, characterized in that it further comprises a catheter body and wherein the ultrasound sensor is attached to the catheter to provide a forward-facing beam. Sensor assembly according to claim 41, characterized in that it further comprises a catheter body and wherein the ultrasound sensor is attached to the catheter to provide a side-facing beam. Sensor assembly according to claim 51, characterized in that the ultrasound sensor is arranged in a recessed form in a catheter wall. Sensor assembly according to claim 52, characterized in that the ultrasound sensor is adapted to provide Doppler readings from a fluid passing over the external catheter surface. Sensor assembly according to claim 52, characterized in that the airtight transparent air-tight seal is formed in an acoustic lens. Sensor assembly according to claim 54, characterized in that the acoustic lens is formed to diffuse the beam generated by the ultrasound sensor.